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  1. .gitattributes +3 -0
  2. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/__init__.py +12 -0
  3. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/__pycache__/inference.cpython-310.pyc +0 -0
  4. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__init__.py +0 -0
  5. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/dpll.cpython-310.pyc +0 -0
  6. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/dpll2.cpython-310.pyc +0 -0
  7. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/lra_theory.cpython-310.pyc +0 -0
  8. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/pycosat_wrapper.cpython-310.pyc +0 -0
  9. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/z3_wrapper.cpython-310.pyc +0 -0
  10. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/dpll.py +308 -0
  11. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/dpll2.py +684 -0
  12. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/lra_theory.py +915 -0
  13. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/minisat22_wrapper.py +46 -0
  14. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/pycosat_wrapper.py +41 -0
  15. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/z3_wrapper.py +115 -0
  16. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/boolalg.py +0 -0
  17. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/inference.py +340 -0
  18. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/tests/__pycache__/__init__.cpython-310.pyc +0 -0
  19. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/tests/__pycache__/test_boolalg.cpython-310.pyc +0 -0
  20. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/utilities/__init__.py +3 -0
  21. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/utilities/__pycache__/__init__.cpython-310.pyc +0 -0
  22. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/utilities/__pycache__/dimacs.cpython-310.pyc +0 -0
  23. evalkit_internvl/lib/python3.10/site-packages/sympy/logic/utilities/dimacs.py +70 -0
  24. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/__init__.cpython-310.pyc +0 -0
  25. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/experimental_lambdify.cpython-310.pyc +0 -0
  26. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/plot.cpython-310.pyc +0 -0
  27. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/plot_implicit.cpython-310.pyc +0 -0
  28. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/plotgrid.cpython-310.pyc +0 -0
  29. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/series.cpython-310.pyc +0 -0
  30. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/textplot.cpython-310.pyc +0 -0
  31. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__init__.py +12 -0
  32. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__pycache__/__init__.cpython-310.pyc +0 -0
  33. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__pycache__/interval_arithmetic.cpython-310.pyc +0 -0
  34. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__pycache__/interval_membership.cpython-310.pyc +0 -0
  35. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__pycache__/lib_interval.cpython-310.pyc +0 -0
  36. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/lib_interval.py +452 -0
  37. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/tests/__pycache__/test_interval_functions.cpython-310.pyc +0 -0
  38. evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/tests/__pycache__/test_series.cpython-310.pyc +0 -0
  39. evalkit_internvl/lib/python3.10/site-packages/sympy/series/__init__.py +23 -0
  40. evalkit_internvl/lib/python3.10/site-packages/sympy/series/acceleration.py +101 -0
  41. evalkit_internvl/lib/python3.10/site-packages/sympy/series/approximants.py +103 -0
  42. evalkit_internvl/lib/python3.10/site-packages/sympy/series/aseries.py +10 -0
  43. evalkit_internvl/lib/python3.10/site-packages/sympy/series/formal.py +1869 -0
  44. evalkit_internvl/lib/python3.10/site-packages/sympy/series/fourier.py +811 -0
  45. evalkit_internvl/lib/python3.10/site-packages/sympy/series/gruntz.py +739 -0
  46. evalkit_internvl/lib/python3.10/site-packages/sympy/series/kauers.py +51 -0
  47. evalkit_internvl/lib/python3.10/site-packages/sympy/series/limits.py +385 -0
  48. evalkit_internvl/lib/python3.10/site-packages/sympy/series/limitseq.py +257 -0
  49. evalkit_internvl/lib/python3.10/site-packages/sympy/series/order.py +517 -0
  50. evalkit_internvl/lib/python3.10/site-packages/sympy/series/residues.py +73 -0
.gitattributes CHANGED
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1638
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  evalkit_tf437/lib/python3.10/site-packages/pydantic_core/_pydantic_core.cpython-310-x86_64-linux-gnu.so filter=lfs diff=lfs merge=lfs -text
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+ infer_4_47_1/lib/python3.10/site-packages/wandb/bin/wandb-core filter=lfs diff=lfs merge=lfs -text
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+ evalkit_internvl/lib/python3.10/site-packages/sympy/solvers/ode/__pycache__/ode.cpython-310.pyc filter=lfs diff=lfs merge=lfs -text
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+ evalkit_internvl/lib/python3.10/site-packages/sympy/solvers/__pycache__/solvers.cpython-310.pyc filter=lfs diff=lfs merge=lfs -text
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/__init__.py ADDED
@@ -0,0 +1,12 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ from .boolalg import (to_cnf, to_dnf, to_nnf, And, Or, Not, Xor, Nand, Nor, Implies,
2
+ Equivalent, ITE, POSform, SOPform, simplify_logic, bool_map, true, false,
3
+ gateinputcount)
4
+ from .inference import satisfiable
5
+
6
+ __all__ = [
7
+ 'to_cnf', 'to_dnf', 'to_nnf', 'And', 'Or', 'Not', 'Xor', 'Nand', 'Nor',
8
+ 'Implies', 'Equivalent', 'ITE', 'POSform', 'SOPform', 'simplify_logic',
9
+ 'bool_map', 'true', 'false', 'gateinputcount',
10
+
11
+ 'satisfiable',
12
+ ]
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__init__.py ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/dpll.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/dpll2.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/lra_theory.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/pycosat_wrapper.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/__pycache__/z3_wrapper.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/dpll.py ADDED
@@ -0,0 +1,308 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """Implementation of DPLL algorithm
2
+
3
+ Further improvements: eliminate calls to pl_true, implement branching rules,
4
+ efficient unit propagation.
5
+
6
+ References:
7
+ - https://en.wikipedia.org/wiki/DPLL_algorithm
8
+ - https://www.researchgate.net/publication/242384772_Implementations_of_the_DPLL_Algorithm
9
+ """
10
+
11
+ from sympy.core.sorting import default_sort_key
12
+ from sympy.logic.boolalg import Or, Not, conjuncts, disjuncts, to_cnf, \
13
+ to_int_repr, _find_predicates
14
+ from sympy.assumptions.cnf import CNF
15
+ from sympy.logic.inference import pl_true, literal_symbol
16
+
17
+
18
+ def dpll_satisfiable(expr):
19
+ """
20
+ Check satisfiability of a propositional sentence.
21
+ It returns a model rather than True when it succeeds
22
+
23
+ >>> from sympy.abc import A, B
24
+ >>> from sympy.logic.algorithms.dpll import dpll_satisfiable
25
+ >>> dpll_satisfiable(A & ~B)
26
+ {A: True, B: False}
27
+ >>> dpll_satisfiable(A & ~A)
28
+ False
29
+
30
+ """
31
+ if not isinstance(expr, CNF):
32
+ clauses = conjuncts(to_cnf(expr))
33
+ else:
34
+ clauses = expr.clauses
35
+ if False in clauses:
36
+ return False
37
+ symbols = sorted(_find_predicates(expr), key=default_sort_key)
38
+ symbols_int_repr = set(range(1, len(symbols) + 1))
39
+ clauses_int_repr = to_int_repr(clauses, symbols)
40
+ result = dpll_int_repr(clauses_int_repr, symbols_int_repr, {})
41
+ if not result:
42
+ return result
43
+ output = {}
44
+ for key in result:
45
+ output.update({symbols[key - 1]: result[key]})
46
+ return output
47
+
48
+
49
+ def dpll(clauses, symbols, model):
50
+ """
51
+ Compute satisfiability in a partial model.
52
+ Clauses is an array of conjuncts.
53
+
54
+ >>> from sympy.abc import A, B, D
55
+ >>> from sympy.logic.algorithms.dpll import dpll
56
+ >>> dpll([A, B, D], [A, B], {D: False})
57
+ False
58
+
59
+ """
60
+ # compute DP kernel
61
+ P, value = find_unit_clause(clauses, model)
62
+ while P:
63
+ model.update({P: value})
64
+ symbols.remove(P)
65
+ if not value:
66
+ P = ~P
67
+ clauses = unit_propagate(clauses, P)
68
+ P, value = find_unit_clause(clauses, model)
69
+ P, value = find_pure_symbol(symbols, clauses)
70
+ while P:
71
+ model.update({P: value})
72
+ symbols.remove(P)
73
+ if not value:
74
+ P = ~P
75
+ clauses = unit_propagate(clauses, P)
76
+ P, value = find_pure_symbol(symbols, clauses)
77
+ # end DP kernel
78
+ unknown_clauses = []
79
+ for c in clauses:
80
+ val = pl_true(c, model)
81
+ if val is False:
82
+ return False
83
+ if val is not True:
84
+ unknown_clauses.append(c)
85
+ if not unknown_clauses:
86
+ return model
87
+ if not clauses:
88
+ return model
89
+ P = symbols.pop()
90
+ model_copy = model.copy()
91
+ model.update({P: True})
92
+ model_copy.update({P: False})
93
+ symbols_copy = symbols[:]
94
+ return (dpll(unit_propagate(unknown_clauses, P), symbols, model) or
95
+ dpll(unit_propagate(unknown_clauses, Not(P)), symbols_copy, model_copy))
96
+
97
+
98
+ def dpll_int_repr(clauses, symbols, model):
99
+ """
100
+ Compute satisfiability in a partial model.
101
+ Arguments are expected to be in integer representation
102
+
103
+ >>> from sympy.logic.algorithms.dpll import dpll_int_repr
104
+ >>> dpll_int_repr([{1}, {2}, {3}], {1, 2}, {3: False})
105
+ False
106
+
107
+ """
108
+ # compute DP kernel
109
+ P, value = find_unit_clause_int_repr(clauses, model)
110
+ while P:
111
+ model.update({P: value})
112
+ symbols.remove(P)
113
+ if not value:
114
+ P = -P
115
+ clauses = unit_propagate_int_repr(clauses, P)
116
+ P, value = find_unit_clause_int_repr(clauses, model)
117
+ P, value = find_pure_symbol_int_repr(symbols, clauses)
118
+ while P:
119
+ model.update({P: value})
120
+ symbols.remove(P)
121
+ if not value:
122
+ P = -P
123
+ clauses = unit_propagate_int_repr(clauses, P)
124
+ P, value = find_pure_symbol_int_repr(symbols, clauses)
125
+ # end DP kernel
126
+ unknown_clauses = []
127
+ for c in clauses:
128
+ val = pl_true_int_repr(c, model)
129
+ if val is False:
130
+ return False
131
+ if val is not True:
132
+ unknown_clauses.append(c)
133
+ if not unknown_clauses:
134
+ return model
135
+ P = symbols.pop()
136
+ model_copy = model.copy()
137
+ model.update({P: True})
138
+ model_copy.update({P: False})
139
+ symbols_copy = symbols.copy()
140
+ return (dpll_int_repr(unit_propagate_int_repr(unknown_clauses, P), symbols, model) or
141
+ dpll_int_repr(unit_propagate_int_repr(unknown_clauses, -P), symbols_copy, model_copy))
142
+
143
+ ### helper methods for DPLL
144
+
145
+
146
+ def pl_true_int_repr(clause, model={}):
147
+ """
148
+ Lightweight version of pl_true.
149
+ Argument clause represents the set of args of an Or clause. This is used
150
+ inside dpll_int_repr, it is not meant to be used directly.
151
+
152
+ >>> from sympy.logic.algorithms.dpll import pl_true_int_repr
153
+ >>> pl_true_int_repr({1, 2}, {1: False})
154
+ >>> pl_true_int_repr({1, 2}, {1: False, 2: False})
155
+ False
156
+
157
+ """
158
+ result = False
159
+ for lit in clause:
160
+ if lit < 0:
161
+ p = model.get(-lit)
162
+ if p is not None:
163
+ p = not p
164
+ else:
165
+ p = model.get(lit)
166
+ if p is True:
167
+ return True
168
+ elif p is None:
169
+ result = None
170
+ return result
171
+
172
+
173
+ def unit_propagate(clauses, symbol):
174
+ """
175
+ Returns an equivalent set of clauses
176
+ If a set of clauses contains the unit clause l, the other clauses are
177
+ simplified by the application of the two following rules:
178
+
179
+ 1. every clause containing l is removed
180
+ 2. in every clause that contains ~l this literal is deleted
181
+
182
+ Arguments are expected to be in CNF.
183
+
184
+ >>> from sympy.abc import A, B, D
185
+ >>> from sympy.logic.algorithms.dpll import unit_propagate
186
+ >>> unit_propagate([A | B, D | ~B, B], B)
187
+ [D, B]
188
+
189
+ """
190
+ output = []
191
+ for c in clauses:
192
+ if c.func != Or:
193
+ output.append(c)
194
+ continue
195
+ for arg in c.args:
196
+ if arg == ~symbol:
197
+ output.append(Or(*[x for x in c.args if x != ~symbol]))
198
+ break
199
+ if arg == symbol:
200
+ break
201
+ else:
202
+ output.append(c)
203
+ return output
204
+
205
+
206
+ def unit_propagate_int_repr(clauses, s):
207
+ """
208
+ Same as unit_propagate, but arguments are expected to be in integer
209
+ representation
210
+
211
+ >>> from sympy.logic.algorithms.dpll import unit_propagate_int_repr
212
+ >>> unit_propagate_int_repr([{1, 2}, {3, -2}, {2}], 2)
213
+ [{3}]
214
+
215
+ """
216
+ negated = {-s}
217
+ return [clause - negated for clause in clauses if s not in clause]
218
+
219
+
220
+ def find_pure_symbol(symbols, unknown_clauses):
221
+ """
222
+ Find a symbol and its value if it appears only as a positive literal
223
+ (or only as a negative) in clauses.
224
+
225
+ >>> from sympy.abc import A, B, D
226
+ >>> from sympy.logic.algorithms.dpll import find_pure_symbol
227
+ >>> find_pure_symbol([A, B, D], [A|~B,~B|~D,D|A])
228
+ (A, True)
229
+
230
+ """
231
+ for sym in symbols:
232
+ found_pos, found_neg = False, False
233
+ for c in unknown_clauses:
234
+ if not found_pos and sym in disjuncts(c):
235
+ found_pos = True
236
+ if not found_neg and Not(sym) in disjuncts(c):
237
+ found_neg = True
238
+ if found_pos != found_neg:
239
+ return sym, found_pos
240
+ return None, None
241
+
242
+
243
+ def find_pure_symbol_int_repr(symbols, unknown_clauses):
244
+ """
245
+ Same as find_pure_symbol, but arguments are expected
246
+ to be in integer representation
247
+
248
+ >>> from sympy.logic.algorithms.dpll import find_pure_symbol_int_repr
249
+ >>> find_pure_symbol_int_repr({1,2,3},
250
+ ... [{1, -2}, {-2, -3}, {3, 1}])
251
+ (1, True)
252
+
253
+ """
254
+ all_symbols = set().union(*unknown_clauses)
255
+ found_pos = all_symbols.intersection(symbols)
256
+ found_neg = all_symbols.intersection([-s for s in symbols])
257
+ for p in found_pos:
258
+ if -p not in found_neg:
259
+ return p, True
260
+ for p in found_neg:
261
+ if -p not in found_pos:
262
+ return -p, False
263
+ return None, None
264
+
265
+
266
+ def find_unit_clause(clauses, model):
267
+ """
268
+ A unit clause has only 1 variable that is not bound in the model.
269
+
270
+ >>> from sympy.abc import A, B, D
271
+ >>> from sympy.logic.algorithms.dpll import find_unit_clause
272
+ >>> find_unit_clause([A | B | D, B | ~D, A | ~B], {A:True})
273
+ (B, False)
274
+
275
+ """
276
+ for clause in clauses:
277
+ num_not_in_model = 0
278
+ for literal in disjuncts(clause):
279
+ sym = literal_symbol(literal)
280
+ if sym not in model:
281
+ num_not_in_model += 1
282
+ P, value = sym, not isinstance(literal, Not)
283
+ if num_not_in_model == 1:
284
+ return P, value
285
+ return None, None
286
+
287
+
288
+ def find_unit_clause_int_repr(clauses, model):
289
+ """
290
+ Same as find_unit_clause, but arguments are expected to be in
291
+ integer representation.
292
+
293
+ >>> from sympy.logic.algorithms.dpll import find_unit_clause_int_repr
294
+ >>> find_unit_clause_int_repr([{1, 2, 3},
295
+ ... {2, -3}, {1, -2}], {1: True})
296
+ (2, False)
297
+
298
+ """
299
+ bound = set(model) | {-sym for sym in model}
300
+ for clause in clauses:
301
+ unbound = clause - bound
302
+ if len(unbound) == 1:
303
+ p = unbound.pop()
304
+ if p < 0:
305
+ return -p, False
306
+ else:
307
+ return p, True
308
+ return None, None
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/dpll2.py ADDED
@@ -0,0 +1,684 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """Implementation of DPLL algorithm
2
+
3
+ Features:
4
+ - Clause learning
5
+ - Watch literal scheme
6
+ - VSIDS heuristic
7
+
8
+ References:
9
+ - https://en.wikipedia.org/wiki/DPLL_algorithm
10
+ """
11
+
12
+ from collections import defaultdict
13
+ from heapq import heappush, heappop
14
+
15
+ from sympy.core.sorting import ordered
16
+ from sympy.assumptions.cnf import EncodedCNF
17
+
18
+ from sympy.logic.algorithms.lra_theory import LRASolver
19
+
20
+
21
+ def dpll_satisfiable(expr, all_models=False, use_lra_theory=False):
22
+ """
23
+ Check satisfiability of a propositional sentence.
24
+ It returns a model rather than True when it succeeds.
25
+ Returns a generator of all models if all_models is True.
26
+
27
+ Examples
28
+ ========
29
+
30
+ >>> from sympy.abc import A, B
31
+ >>> from sympy.logic.algorithms.dpll2 import dpll_satisfiable
32
+ >>> dpll_satisfiable(A & ~B)
33
+ {A: True, B: False}
34
+ >>> dpll_satisfiable(A & ~A)
35
+ False
36
+
37
+ """
38
+ if not isinstance(expr, EncodedCNF):
39
+ exprs = EncodedCNF()
40
+ exprs.add_prop(expr)
41
+ expr = exprs
42
+
43
+ # Return UNSAT when False (encoded as 0) is present in the CNF
44
+ if {0} in expr.data:
45
+ if all_models:
46
+ return (f for f in [False])
47
+ return False
48
+
49
+ if use_lra_theory:
50
+ lra, immediate_conflicts = LRASolver.from_encoded_cnf(expr)
51
+ else:
52
+ lra = None
53
+ immediate_conflicts = []
54
+ solver = SATSolver(expr.data + immediate_conflicts, expr.variables, set(), expr.symbols, lra_theory=lra)
55
+ models = solver._find_model()
56
+
57
+ if all_models:
58
+ return _all_models(models)
59
+
60
+ try:
61
+ return next(models)
62
+ except StopIteration:
63
+ return False
64
+
65
+ # Uncomment to confirm the solution is valid (hitting set for the clauses)
66
+ #else:
67
+ #for cls in clauses_int_repr:
68
+ #assert solver.var_settings.intersection(cls)
69
+
70
+
71
+ def _all_models(models):
72
+ satisfiable = False
73
+ try:
74
+ while True:
75
+ yield next(models)
76
+ satisfiable = True
77
+ except StopIteration:
78
+ if not satisfiable:
79
+ yield False
80
+
81
+
82
+ class SATSolver:
83
+ """
84
+ Class for representing a SAT solver capable of
85
+ finding a model to a boolean theory in conjunctive
86
+ normal form.
87
+ """
88
+
89
+ def __init__(self, clauses, variables, var_settings, symbols=None,
90
+ heuristic='vsids', clause_learning='none', INTERVAL=500,
91
+ lra_theory = None):
92
+
93
+ self.var_settings = var_settings
94
+ self.heuristic = heuristic
95
+ self.is_unsatisfied = False
96
+ self._unit_prop_queue = []
97
+ self.update_functions = []
98
+ self.INTERVAL = INTERVAL
99
+
100
+ if symbols is None:
101
+ self.symbols = list(ordered(variables))
102
+ else:
103
+ self.symbols = symbols
104
+
105
+ self._initialize_variables(variables)
106
+ self._initialize_clauses(clauses)
107
+
108
+ if 'vsids' == heuristic:
109
+ self._vsids_init()
110
+ self.heur_calculate = self._vsids_calculate
111
+ self.heur_lit_assigned = self._vsids_lit_assigned
112
+ self.heur_lit_unset = self._vsids_lit_unset
113
+ self.heur_clause_added = self._vsids_clause_added
114
+
115
+ # Note: Uncomment this if/when clause learning is enabled
116
+ #self.update_functions.append(self._vsids_decay)
117
+
118
+ else:
119
+ raise NotImplementedError
120
+
121
+ if 'simple' == clause_learning:
122
+ self.add_learned_clause = self._simple_add_learned_clause
123
+ self.compute_conflict = self._simple_compute_conflict
124
+ self.update_functions.append(self._simple_clean_clauses)
125
+ elif 'none' == clause_learning:
126
+ self.add_learned_clause = lambda x: None
127
+ self.compute_conflict = lambda: None
128
+ else:
129
+ raise NotImplementedError
130
+
131
+ # Create the base level
132
+ self.levels = [Level(0)]
133
+ self._current_level.varsettings = var_settings
134
+
135
+ # Keep stats
136
+ self.num_decisions = 0
137
+ self.num_learned_clauses = 0
138
+ self.original_num_clauses = len(self.clauses)
139
+
140
+ self.lra = lra_theory
141
+
142
+ def _initialize_variables(self, variables):
143
+ """Set up the variable data structures needed."""
144
+ self.sentinels = defaultdict(set)
145
+ self.occurrence_count = defaultdict(int)
146
+ self.variable_set = [False] * (len(variables) + 1)
147
+
148
+ def _initialize_clauses(self, clauses):
149
+ """Set up the clause data structures needed.
150
+
151
+ For each clause, the following changes are made:
152
+ - Unit clauses are queued for propagation right away.
153
+ - Non-unit clauses have their first and last literals set as sentinels.
154
+ - The number of clauses a literal appears in is computed.
155
+ """
156
+ self.clauses = [list(clause) for clause in clauses]
157
+
158
+ for i, clause in enumerate(self.clauses):
159
+
160
+ # Handle the unit clauses
161
+ if 1 == len(clause):
162
+ self._unit_prop_queue.append(clause[0])
163
+ continue
164
+
165
+ self.sentinels[clause[0]].add(i)
166
+ self.sentinels[clause[-1]].add(i)
167
+
168
+ for lit in clause:
169
+ self.occurrence_count[lit] += 1
170
+
171
+ def _find_model(self):
172
+ """
173
+ Main DPLL loop. Returns a generator of models.
174
+
175
+ Variables are chosen successively, and assigned to be either
176
+ True or False. If a solution is not found with this setting,
177
+ the opposite is chosen and the search continues. The solver
178
+ halts when every variable has a setting.
179
+
180
+ Examples
181
+ ========
182
+
183
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
184
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
185
+ ... {3, -2}], {1, 2, 3}, set())
186
+ >>> list(l._find_model())
187
+ [{1: True, 2: False, 3: False}, {1: True, 2: True, 3: True}]
188
+
189
+ >>> from sympy.abc import A, B, C
190
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
191
+ ... {3, -2}], {1, 2, 3}, set(), [A, B, C])
192
+ >>> list(l._find_model())
193
+ [{A: True, B: False, C: False}, {A: True, B: True, C: True}]
194
+
195
+ """
196
+
197
+ # We use this variable to keep track of if we should flip a
198
+ # variable setting in successive rounds
199
+ flip_var = False
200
+
201
+ # Check if unit prop says the theory is unsat right off the bat
202
+ self._simplify()
203
+ if self.is_unsatisfied:
204
+ return
205
+
206
+ # While the theory still has clauses remaining
207
+ while True:
208
+ # Perform cleanup / fixup at regular intervals
209
+ if self.num_decisions % self.INTERVAL == 0:
210
+ for func in self.update_functions:
211
+ func()
212
+
213
+ if flip_var:
214
+ # We have just backtracked and we are trying to opposite literal
215
+ flip_var = False
216
+ lit = self._current_level.decision
217
+
218
+ else:
219
+ # Pick a literal to set
220
+ lit = self.heur_calculate()
221
+ self.num_decisions += 1
222
+
223
+ # Stopping condition for a satisfying theory
224
+ if 0 == lit:
225
+
226
+ # check if assignment satisfies lra theory
227
+ if self.lra:
228
+ for enc_var in self.var_settings:
229
+ res = self.lra.assert_lit(enc_var)
230
+ if res is not None:
231
+ break
232
+ res = self.lra.check()
233
+ self.lra.reset_bounds()
234
+ else:
235
+ res = None
236
+ if res is None or res[0]:
237
+ yield {self.symbols[abs(lit) - 1]:
238
+ lit > 0 for lit in self.var_settings}
239
+ else:
240
+ self._simple_add_learned_clause(res[1])
241
+
242
+ while self._current_level.flipped:
243
+ self._undo()
244
+ if len(self.levels) == 1:
245
+ return
246
+ flip_lit = -self._current_level.decision
247
+ self._undo()
248
+ self.levels.append(Level(flip_lit, flipped=True))
249
+ flip_var = True
250
+ continue
251
+
252
+ # Start the new decision level
253
+ self.levels.append(Level(lit))
254
+
255
+ # Assign the literal, updating the clauses it satisfies
256
+ self._assign_literal(lit)
257
+
258
+ # _simplify the theory
259
+ self._simplify()
260
+
261
+ # Check if we've made the theory unsat
262
+ if self.is_unsatisfied:
263
+
264
+ self.is_unsatisfied = False
265
+
266
+ # We unroll all of the decisions until we can flip a literal
267
+ while self._current_level.flipped:
268
+ self._undo()
269
+
270
+ # If we've unrolled all the way, the theory is unsat
271
+ if 1 == len(self.levels):
272
+ return
273
+
274
+ # Detect and add a learned clause
275
+ self.add_learned_clause(self.compute_conflict())
276
+
277
+ # Try the opposite setting of the most recent decision
278
+ flip_lit = -self._current_level.decision
279
+ self._undo()
280
+ self.levels.append(Level(flip_lit, flipped=True))
281
+ flip_var = True
282
+
283
+ ########################
284
+ # Helper Methods #
285
+ ########################
286
+ @property
287
+ def _current_level(self):
288
+ """The current decision level data structure
289
+
290
+ Examples
291
+ ========
292
+
293
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
294
+ >>> l = SATSolver([{1}, {2}], {1, 2}, set())
295
+ >>> next(l._find_model())
296
+ {1: True, 2: True}
297
+ >>> l._current_level.decision
298
+ 0
299
+ >>> l._current_level.flipped
300
+ False
301
+ >>> l._current_level.var_settings
302
+ {1, 2}
303
+
304
+ """
305
+ return self.levels[-1]
306
+
307
+ def _clause_sat(self, cls):
308
+ """Check if a clause is satisfied by the current variable setting.
309
+
310
+ Examples
311
+ ========
312
+
313
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
314
+ >>> l = SATSolver([{1}, {-1}], {1}, set())
315
+ >>> try:
316
+ ... next(l._find_model())
317
+ ... except StopIteration:
318
+ ... pass
319
+ >>> l._clause_sat(0)
320
+ False
321
+ >>> l._clause_sat(1)
322
+ True
323
+
324
+ """
325
+ for lit in self.clauses[cls]:
326
+ if lit in self.var_settings:
327
+ return True
328
+ return False
329
+
330
+ def _is_sentinel(self, lit, cls):
331
+ """Check if a literal is a sentinel of a given clause.
332
+
333
+ Examples
334
+ ========
335
+
336
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
337
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
338
+ ... {3, -2}], {1, 2, 3}, set())
339
+ >>> next(l._find_model())
340
+ {1: True, 2: False, 3: False}
341
+ >>> l._is_sentinel(2, 3)
342
+ True
343
+ >>> l._is_sentinel(-3, 1)
344
+ False
345
+
346
+ """
347
+ return cls in self.sentinels[lit]
348
+
349
+ def _assign_literal(self, lit):
350
+ """Make a literal assignment.
351
+
352
+ The literal assignment must be recorded as part of the current
353
+ decision level. Additionally, if the literal is marked as a
354
+ sentinel of any clause, then a new sentinel must be chosen. If
355
+ this is not possible, then unit propagation is triggered and
356
+ another literal is added to the queue to be set in the future.
357
+
358
+ Examples
359
+ ========
360
+
361
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
362
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
363
+ ... {3, -2}], {1, 2, 3}, set())
364
+ >>> next(l._find_model())
365
+ {1: True, 2: False, 3: False}
366
+ >>> l.var_settings
367
+ {-3, -2, 1}
368
+
369
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
370
+ ... {3, -2}], {1, 2, 3}, set())
371
+ >>> l._assign_literal(-1)
372
+ >>> try:
373
+ ... next(l._find_model())
374
+ ... except StopIteration:
375
+ ... pass
376
+ >>> l.var_settings
377
+ {-1}
378
+
379
+ """
380
+ self.var_settings.add(lit)
381
+ self._current_level.var_settings.add(lit)
382
+ self.variable_set[abs(lit)] = True
383
+ self.heur_lit_assigned(lit)
384
+
385
+ sentinel_list = list(self.sentinels[-lit])
386
+
387
+ for cls in sentinel_list:
388
+ if not self._clause_sat(cls):
389
+ other_sentinel = None
390
+ for newlit in self.clauses[cls]:
391
+ if newlit != -lit:
392
+ if self._is_sentinel(newlit, cls):
393
+ other_sentinel = newlit
394
+ elif not self.variable_set[abs(newlit)]:
395
+ self.sentinels[-lit].remove(cls)
396
+ self.sentinels[newlit].add(cls)
397
+ other_sentinel = None
398
+ break
399
+
400
+ # Check if no sentinel update exists
401
+ if other_sentinel:
402
+ self._unit_prop_queue.append(other_sentinel)
403
+
404
+ def _undo(self):
405
+ """
406
+ _undo the changes of the most recent decision level.
407
+
408
+ Examples
409
+ ========
410
+
411
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
412
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
413
+ ... {3, -2}], {1, 2, 3}, set())
414
+ >>> next(l._find_model())
415
+ {1: True, 2: False, 3: False}
416
+ >>> level = l._current_level
417
+ >>> level.decision, level.var_settings, level.flipped
418
+ (-3, {-3, -2}, False)
419
+ >>> l._undo()
420
+ >>> level = l._current_level
421
+ >>> level.decision, level.var_settings, level.flipped
422
+ (0, {1}, False)
423
+
424
+ """
425
+ # Undo the variable settings
426
+ for lit in self._current_level.var_settings:
427
+ self.var_settings.remove(lit)
428
+ self.heur_lit_unset(lit)
429
+ self.variable_set[abs(lit)] = False
430
+
431
+ # Pop the level off the stack
432
+ self.levels.pop()
433
+
434
+ #########################
435
+ # Propagation #
436
+ #########################
437
+ """
438
+ Propagation methods should attempt to soundly simplify the boolean
439
+ theory, and return True if any simplification occurred and False
440
+ otherwise.
441
+ """
442
+ def _simplify(self):
443
+ """Iterate over the various forms of propagation to simplify the theory.
444
+
445
+ Examples
446
+ ========
447
+
448
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
449
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
450
+ ... {3, -2}], {1, 2, 3}, set())
451
+ >>> l.variable_set
452
+ [False, False, False, False]
453
+ >>> l.sentinels
454
+ {-3: {0, 2}, -2: {3, 4}, 2: {0, 3}, 3: {2, 4}}
455
+
456
+ >>> l._simplify()
457
+
458
+ >>> l.variable_set
459
+ [False, True, False, False]
460
+ >>> l.sentinels
461
+ {-3: {0, 2}, -2: {3, 4}, -1: set(), 2: {0, 3},
462
+ ...3: {2, 4}}
463
+
464
+ """
465
+ changed = True
466
+ while changed:
467
+ changed = False
468
+ changed |= self._unit_prop()
469
+ changed |= self._pure_literal()
470
+
471
+ def _unit_prop(self):
472
+ """Perform unit propagation on the current theory."""
473
+ result = len(self._unit_prop_queue) > 0
474
+ while self._unit_prop_queue:
475
+ next_lit = self._unit_prop_queue.pop()
476
+ if -next_lit in self.var_settings:
477
+ self.is_unsatisfied = True
478
+ self._unit_prop_queue = []
479
+ return False
480
+ else:
481
+ self._assign_literal(next_lit)
482
+
483
+ return result
484
+
485
+ def _pure_literal(self):
486
+ """Look for pure literals and assign them when found."""
487
+ return False
488
+
489
+ #########################
490
+ # Heuristics #
491
+ #########################
492
+ def _vsids_init(self):
493
+ """Initialize the data structures needed for the VSIDS heuristic."""
494
+ self.lit_heap = []
495
+ self.lit_scores = {}
496
+
497
+ for var in range(1, len(self.variable_set)):
498
+ self.lit_scores[var] = float(-self.occurrence_count[var])
499
+ self.lit_scores[-var] = float(-self.occurrence_count[-var])
500
+ heappush(self.lit_heap, (self.lit_scores[var], var))
501
+ heappush(self.lit_heap, (self.lit_scores[-var], -var))
502
+
503
+ def _vsids_decay(self):
504
+ """Decay the VSIDS scores for every literal.
505
+
506
+ Examples
507
+ ========
508
+
509
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
510
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
511
+ ... {3, -2}], {1, 2, 3}, set())
512
+
513
+ >>> l.lit_scores
514
+ {-3: -2.0, -2: -2.0, -1: 0.0, 1: 0.0, 2: -2.0, 3: -2.0}
515
+
516
+ >>> l._vsids_decay()
517
+
518
+ >>> l.lit_scores
519
+ {-3: -1.0, -2: -1.0, -1: 0.0, 1: 0.0, 2: -1.0, 3: -1.0}
520
+
521
+ """
522
+ # We divide every literal score by 2 for a decay factor
523
+ # Note: This doesn't change the heap property
524
+ for lit in self.lit_scores.keys():
525
+ self.lit_scores[lit] /= 2.0
526
+
527
+ def _vsids_calculate(self):
528
+ """
529
+ VSIDS Heuristic Calculation
530
+
531
+ Examples
532
+ ========
533
+
534
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
535
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
536
+ ... {3, -2}], {1, 2, 3}, set())
537
+
538
+ >>> l.lit_heap
539
+ [(-2.0, -3), (-2.0, 2), (-2.0, -2), (0.0, 1), (-2.0, 3), (0.0, -1)]
540
+
541
+ >>> l._vsids_calculate()
542
+ -3
543
+
544
+ >>> l.lit_heap
545
+ [(-2.0, -2), (-2.0, 2), (0.0, -1), (0.0, 1), (-2.0, 3)]
546
+
547
+ """
548
+ if len(self.lit_heap) == 0:
549
+ return 0
550
+
551
+ # Clean out the front of the heap as long the variables are set
552
+ while self.variable_set[abs(self.lit_heap[0][1])]:
553
+ heappop(self.lit_heap)
554
+ if len(self.lit_heap) == 0:
555
+ return 0
556
+
557
+ return heappop(self.lit_heap)[1]
558
+
559
+ def _vsids_lit_assigned(self, lit):
560
+ """Handle the assignment of a literal for the VSIDS heuristic."""
561
+ pass
562
+
563
+ def _vsids_lit_unset(self, lit):
564
+ """Handle the unsetting of a literal for the VSIDS heuristic.
565
+
566
+ Examples
567
+ ========
568
+
569
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
570
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
571
+ ... {3, -2}], {1, 2, 3}, set())
572
+ >>> l.lit_heap
573
+ [(-2.0, -3), (-2.0, 2), (-2.0, -2), (0.0, 1), (-2.0, 3), (0.0, -1)]
574
+
575
+ >>> l._vsids_lit_unset(2)
576
+
577
+ >>> l.lit_heap
578
+ [(-2.0, -3), (-2.0, -2), (-2.0, -2), (-2.0, 2), (-2.0, 3), (0.0, -1),
579
+ ...(-2.0, 2), (0.0, 1)]
580
+
581
+ """
582
+ var = abs(lit)
583
+ heappush(self.lit_heap, (self.lit_scores[var], var))
584
+ heappush(self.lit_heap, (self.lit_scores[-var], -var))
585
+
586
+ def _vsids_clause_added(self, cls):
587
+ """Handle the addition of a new clause for the VSIDS heuristic.
588
+
589
+ Examples
590
+ ========
591
+
592
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
593
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
594
+ ... {3, -2}], {1, 2, 3}, set())
595
+
596
+ >>> l.num_learned_clauses
597
+ 0
598
+ >>> l.lit_scores
599
+ {-3: -2.0, -2: -2.0, -1: 0.0, 1: 0.0, 2: -2.0, 3: -2.0}
600
+
601
+ >>> l._vsids_clause_added({2, -3})
602
+
603
+ >>> l.num_learned_clauses
604
+ 1
605
+ >>> l.lit_scores
606
+ {-3: -1.0, -2: -2.0, -1: 0.0, 1: 0.0, 2: -1.0, 3: -2.0}
607
+
608
+ """
609
+ self.num_learned_clauses += 1
610
+ for lit in cls:
611
+ self.lit_scores[lit] += 1
612
+
613
+ ########################
614
+ # Clause Learning #
615
+ ########################
616
+ def _simple_add_learned_clause(self, cls):
617
+ """Add a new clause to the theory.
618
+
619
+ Examples
620
+ ========
621
+
622
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
623
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
624
+ ... {3, -2}], {1, 2, 3}, set())
625
+
626
+ >>> l.num_learned_clauses
627
+ 0
628
+ >>> l.clauses
629
+ [[2, -3], [1], [3, -3], [2, -2], [3, -2]]
630
+ >>> l.sentinels
631
+ {-3: {0, 2}, -2: {3, 4}, 2: {0, 3}, 3: {2, 4}}
632
+
633
+ >>> l._simple_add_learned_clause([3])
634
+
635
+ >>> l.clauses
636
+ [[2, -3], [1], [3, -3], [2, -2], [3, -2], [3]]
637
+ >>> l.sentinels
638
+ {-3: {0, 2}, -2: {3, 4}, 2: {0, 3}, 3: {2, 4, 5}}
639
+
640
+ """
641
+ cls_num = len(self.clauses)
642
+ self.clauses.append(cls)
643
+
644
+ for lit in cls:
645
+ self.occurrence_count[lit] += 1
646
+
647
+ self.sentinels[cls[0]].add(cls_num)
648
+ self.sentinels[cls[-1]].add(cls_num)
649
+
650
+ self.heur_clause_added(cls)
651
+
652
+ def _simple_compute_conflict(self):
653
+ """ Build a clause representing the fact that at least one decision made
654
+ so far is wrong.
655
+
656
+ Examples
657
+ ========
658
+
659
+ >>> from sympy.logic.algorithms.dpll2 import SATSolver
660
+ >>> l = SATSolver([{2, -3}, {1}, {3, -3}, {2, -2},
661
+ ... {3, -2}], {1, 2, 3}, set())
662
+ >>> next(l._find_model())
663
+ {1: True, 2: False, 3: False}
664
+ >>> l._simple_compute_conflict()
665
+ [3]
666
+
667
+ """
668
+ return [-(level.decision) for level in self.levels[1:]]
669
+
670
+ def _simple_clean_clauses(self):
671
+ """Clean up learned clauses."""
672
+ pass
673
+
674
+
675
+ class Level:
676
+ """
677
+ Represents a single level in the DPLL algorithm, and contains
678
+ enough information for a sound backtracking procedure.
679
+ """
680
+
681
+ def __init__(self, decision, flipped=False):
682
+ self.decision = decision
683
+ self.var_settings = set()
684
+ self.flipped = flipped
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/lra_theory.py ADDED
@@ -0,0 +1,915 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """Implements "A Fast Linear-Arithmetic Solver for DPLL(T)"
2
+
3
+ The LRASolver class defined in this file can be used
4
+ in conjunction with a SAT solver to check the
5
+ satisfiability of formulas involving inequalities.
6
+
7
+ Here's an example of how that would work:
8
+
9
+ Suppose you want to check the satisfiability of
10
+ the following formula:
11
+
12
+ >>> from sympy.core.relational import Eq
13
+ >>> from sympy.abc import x, y
14
+ >>> f = ((x > 0) | (x < 0)) & (Eq(x, 0) | Eq(y, 1)) & (~Eq(y, 1) | Eq(1, 2))
15
+
16
+ First a preprocessing step should be done on f. During preprocessing,
17
+ f should be checked for any predicates such as `Q.prime` that can't be
18
+ handled. Also unequality like `~Eq(y, 1)` should be split.
19
+
20
+ I should mention that the paper says to split both equalities and
21
+ unequality, but this implementation only requires that unequality
22
+ be split.
23
+
24
+ >>> f = ((x > 0) | (x < 0)) & (Eq(x, 0) | Eq(y, 1)) & ((y < 1) | (y > 1) | Eq(1, 2))
25
+
26
+ Then an LRASolver instance needs to be initialized with this formula.
27
+
28
+ >>> from sympy.assumptions.cnf import CNF, EncodedCNF
29
+ >>> from sympy.assumptions.ask import Q
30
+ >>> from sympy.logic.algorithms.lra_theory import LRASolver
31
+ >>> cnf = CNF.from_prop(f)
32
+ >>> enc = EncodedCNF()
33
+ >>> enc.add_from_cnf(cnf)
34
+ >>> lra, conflicts = LRASolver.from_encoded_cnf(enc)
35
+
36
+ Any immediate one-lital conflicts clauses will be detected here.
37
+ In this example, `~Eq(1, 2)` is one such conflict clause. We'll
38
+ want to add it to `f` so that the SAT solver is forced to
39
+ assign Eq(1, 2) to False.
40
+
41
+ >>> f = f & ~Eq(1, 2)
42
+
43
+ Now that the one-literal conflict clauses have been added
44
+ and an lra object has been initialized, we can pass `f`
45
+ to a SAT solver. The SAT solver will give us a satisfying
46
+ assignment such as:
47
+
48
+ (1 = 2): False
49
+ (y = 1): True
50
+ (y < 1): True
51
+ (y > 1): True
52
+ (x = 0): True
53
+ (x < 0): True
54
+ (x > 0): True
55
+
56
+ Next you would pass this assignment to the LRASolver
57
+ which will be able to determine that this particular
58
+ assignment is satisfiable or not.
59
+
60
+ Note that since EncodedCNF is inherently non-deterministic,
61
+ the int each predicate is encoded as is not consistent. As a
62
+ result, the code bellow likely does not reflect the assignment
63
+ given above.
64
+
65
+ >>> lra.assert_lit(-1) #doctest: +SKIP
66
+ >>> lra.assert_lit(2) #doctest: +SKIP
67
+ >>> lra.assert_lit(3) #doctest: +SKIP
68
+ >>> lra.assert_lit(4) #doctest: +SKIP
69
+ >>> lra.assert_lit(5) #doctest: +SKIP
70
+ >>> lra.assert_lit(6) #doctest: +SKIP
71
+ >>> lra.assert_lit(7) #doctest: +SKIP
72
+ >>> is_sat, conflict_or_assignment = lra.check()
73
+
74
+ As the particular assignment suggested is not satisfiable,
75
+ the LRASolver will return unsat and a conflict clause when
76
+ given that assignment. The conflict clause will always be
77
+ minimal, but there can be multiple minimal conflict clauses.
78
+ One possible conflict clause could be `~(x < 0) | ~(x > 0)`.
79
+
80
+ We would then add whatever conflict clause is given to
81
+ `f` to prevent the SAT solver from coming up with an
82
+ assignment with the same conflicting literals. In this case,
83
+ the conflict clause `~(x < 0) | ~(x > 0)` would prevent
84
+ any assignment where both (x < 0) and (x > 0) were both
85
+ true.
86
+
87
+ The SAT solver would then find another assignment
88
+ and we would check that assignment with the LRASolver
89
+ and so on. Eventually either a satisfying assignment
90
+ that the SAT solver and LRASolver agreed on would be found
91
+ or enough conflict clauses would be added so that the
92
+ boolean formula was unsatisfiable.
93
+
94
+
95
+ This implementation is based on [1]_, which includes a
96
+ detailed explanation of the algorithm and pseudocode
97
+ for the most important functions.
98
+
99
+ [1]_ also explains how backtracking and theory propagation
100
+ could be implemented to speed up the current implementation,
101
+ but these are not currently implemented.
102
+
103
+ TODO:
104
+ - Handle non-rational real numbers
105
+ - Handle positive and negative infinity
106
+ - Implement backtracking and theory proposition
107
+ - Simplify matrix by removing unused variables using Gaussian elimination
108
+
109
+ References
110
+ ==========
111
+
112
+ .. [1] Dutertre, B., de Moura, L.:
113
+ A Fast Linear-Arithmetic Solver for DPLL(T)
114
+ https://link.springer.com/chapter/10.1007/11817963_11
115
+ """
116
+ from sympy.solvers.solveset import linear_eq_to_matrix
117
+ from sympy.matrices.dense import eye
118
+ from sympy.assumptions import Predicate
119
+ from sympy.assumptions.assume import AppliedPredicate
120
+ from sympy.assumptions.ask import Q
121
+ from sympy.core import Dummy
122
+ from sympy.core.mul import Mul
123
+ from sympy.core.add import Add
124
+ from sympy.core.relational import Eq, Ne
125
+ from sympy.core.sympify import sympify
126
+ from sympy.core.singleton import S
127
+ from sympy.core.numbers import Rational, oo
128
+ from sympy.matrices.dense import Matrix
129
+
130
+ class UnhandledInput(Exception):
131
+ """
132
+ Raised while creating an LRASolver if non-linearity
133
+ or non-rational numbers are present.
134
+ """
135
+
136
+ # predicates that LRASolver understands and makes use of
137
+ ALLOWED_PRED = {Q.eq, Q.gt, Q.lt, Q.le, Q.ge}
138
+
139
+ # if true ~Q.gt(x, y) implies Q.le(x, y)
140
+ HANDLE_NEGATION = True
141
+
142
+ class LRASolver():
143
+ """
144
+ Linear Arithmetic Solver for DPLL(T) implemented with an algorithm based on
145
+ the Dual Simplex method. Uses Bland's pivoting rule to avoid cycling.
146
+
147
+ References
148
+ ==========
149
+
150
+ .. [1] Dutertre, B., de Moura, L.:
151
+ A Fast Linear-Arithmetic Solver for DPLL(T)
152
+ https://link.springer.com/chapter/10.1007/11817963_11
153
+ """
154
+
155
+ def __init__(self, A, slack_variables, nonslack_variables, enc_to_boundary, s_subs, testing_mode):
156
+ """
157
+ Use the "from_encoded_cnf" method to create a new LRASolver.
158
+ """
159
+ self.run_checks = testing_mode
160
+ self.s_subs = s_subs # used only for test_lra_theory.test_random_problems
161
+
162
+ if any(not isinstance(a, Rational) for a in A):
163
+ raise UnhandledInput("Non-rational numbers are not handled")
164
+ if any(not isinstance(b.bound, Rational) for b in enc_to_boundary.values()):
165
+ raise UnhandledInput("Non-rational numbers are not handled")
166
+ m, n = len(slack_variables), len(slack_variables)+len(nonslack_variables)
167
+ if m != 0:
168
+ assert A.shape == (m, n)
169
+ if self.run_checks:
170
+ assert A[:, n-m:] == -eye(m)
171
+
172
+ self.enc_to_boundary = enc_to_boundary # mapping of int to Boundry objects
173
+ self.boundary_to_enc = {value: key for key, value in enc_to_boundary.items()}
174
+ self.A = A
175
+ self.slack = slack_variables
176
+ self.nonslack = nonslack_variables
177
+ self.all_var = nonslack_variables + slack_variables
178
+
179
+ self.slack_set = set(slack_variables)
180
+
181
+ self.is_sat = True # While True, all constraints asserted so far are satisfiable
182
+ self.result = None # always one of: (True, assignment), (False, conflict clause), None
183
+
184
+ @staticmethod
185
+ def from_encoded_cnf(encoded_cnf, testing_mode=False):
186
+ """
187
+ Creates an LRASolver from an EncodedCNF object
188
+ and a list of conflict clauses for propositions
189
+ that can be simplified to True or False.
190
+
191
+ Parameters
192
+ ==========
193
+
194
+ encoded_cnf : EncodedCNF
195
+
196
+ testing_mode : bool
197
+ Setting testing_mode to True enables some slow assert statements
198
+ and sorting to reduce nonterministic behavior.
199
+
200
+ Returns
201
+ =======
202
+
203
+ (lra, conflicts)
204
+
205
+ lra : LRASolver
206
+
207
+ conflicts : list
208
+ Contains a one-literal conflict clause for each proposition
209
+ that can be simplified to True or False.
210
+
211
+ Example
212
+ =======
213
+
214
+ >>> from sympy.core.relational import Eq
215
+ >>> from sympy.assumptions.cnf import CNF, EncodedCNF
216
+ >>> from sympy.assumptions.ask import Q
217
+ >>> from sympy.logic.algorithms.lra_theory import LRASolver
218
+ >>> from sympy.abc import x, y, z
219
+ >>> phi = (x >= 0) & ((x + y <= 2) | (x + 2 * y - z >= 6))
220
+ >>> phi = phi & (Eq(x + y, 2) | (x + 2 * y - z > 4))
221
+ >>> phi = phi & Q.gt(2, 1)
222
+ >>> cnf = CNF.from_prop(phi)
223
+ >>> enc = EncodedCNF()
224
+ >>> enc.from_cnf(cnf)
225
+ >>> lra, conflicts = LRASolver.from_encoded_cnf(enc, testing_mode=True)
226
+ >>> lra #doctest: +SKIP
227
+ <sympy.logic.algorithms.lra_theory.LRASolver object at 0x7fdcb0e15b70>
228
+ >>> conflicts #doctest: +SKIP
229
+ [[4]]
230
+ """
231
+ # This function has three main jobs:
232
+ # - raise errors if the input formula is not handled
233
+ # - preprocesses the formula into a matirx and single variable constraints
234
+ # - create one-literal conflict clauses from predicates that are always True
235
+ # or always False such as Q.gt(3, 2)
236
+ #
237
+ # See the preprocessing section of "A Fast Linear-Arithmetic Solver for DPLL(T)"
238
+ # for an explanation of how the formula is converted into a matrix
239
+ # and a set of single variable constraints.
240
+
241
+ encoding = {} # maps int to boundary
242
+ A = []
243
+
244
+ basic = []
245
+ s_count = 0
246
+ s_subs = {}
247
+ nonbasic = []
248
+
249
+ if testing_mode:
250
+ # sort to reduce nondeterminism
251
+ encoded_cnf_items = sorted(encoded_cnf.encoding.items(), key=lambda x: str(x))
252
+ else:
253
+ encoded_cnf_items = encoded_cnf.encoding.items()
254
+
255
+ empty_var = Dummy()
256
+ var_to_lra_var = {}
257
+ conflicts = []
258
+
259
+ for prop, enc in encoded_cnf_items:
260
+ if isinstance(prop, Predicate):
261
+ prop = prop(empty_var)
262
+ if not isinstance(prop, AppliedPredicate):
263
+ if prop == True:
264
+ conflicts.append([enc])
265
+ continue
266
+ if prop == False:
267
+ conflicts.append([-enc])
268
+ continue
269
+
270
+ raise ValueError(f"Unhandled Predicate: {prop}")
271
+
272
+ assert prop.function in ALLOWED_PRED
273
+ if prop.lhs == S.NaN or prop.rhs == S.NaN:
274
+ raise ValueError(f"{prop} contains nan")
275
+ if prop.lhs.is_imaginary or prop.rhs.is_imaginary:
276
+ raise UnhandledInput(f"{prop} contains an imaginary component")
277
+ if prop.lhs == oo or prop.rhs == oo:
278
+ raise UnhandledInput(f"{prop} contains infinity")
279
+
280
+ prop = _eval_binrel(prop) # simplify variable-less quantities to True / False if possible
281
+ if prop == True:
282
+ conflicts.append([enc])
283
+ continue
284
+ elif prop == False:
285
+ conflicts.append([-enc])
286
+ continue
287
+ elif prop is None:
288
+ raise UnhandledInput(f"{prop} could not be simplified")
289
+
290
+ expr = prop.lhs - prop.rhs
291
+ if prop.function in [Q.ge, Q.gt]:
292
+ expr = -expr
293
+
294
+ # expr should be less than (or equal to) 0
295
+ # otherwise prop is False
296
+ if prop.function in [Q.le, Q.ge]:
297
+ bool = (expr <= 0)
298
+ elif prop.function in [Q.lt, Q.gt]:
299
+ bool = (expr < 0)
300
+ else:
301
+ assert prop.function == Q.eq
302
+ bool = Eq(expr, 0)
303
+
304
+ if bool == True:
305
+ conflicts.append([enc])
306
+ continue
307
+ elif bool == False:
308
+ conflicts.append([-enc])
309
+ continue
310
+
311
+
312
+ vars, const = _sep_const_terms(expr) # example: (2x + 3y + 2) --> (2x + 3y), (2)
313
+ vars, var_coeff = _sep_const_coeff(vars) # examples: (2x) --> (x, 2); (2x + 3y) --> (2x + 3y), (1)
314
+ const = const / var_coeff
315
+
316
+ terms = _list_terms(vars) # example: (2x + 3y) --> [2x, 3y]
317
+ for term in terms:
318
+ term, _ = _sep_const_coeff(term)
319
+ assert len(term.free_symbols) > 0
320
+ if term not in var_to_lra_var:
321
+ var_to_lra_var[term] = LRAVariable(term)
322
+ nonbasic.append(term)
323
+
324
+ if len(terms) > 1:
325
+ if vars not in s_subs:
326
+ s_count += 1
327
+ d = Dummy(f"s{s_count}")
328
+ var_to_lra_var[d] = LRAVariable(d)
329
+ basic.append(d)
330
+ s_subs[vars] = d
331
+ A.append(vars - d)
332
+ var = s_subs[vars]
333
+ else:
334
+ var = terms[0]
335
+
336
+ assert var_coeff != 0
337
+
338
+ equality = prop.function == Q.eq
339
+ upper = var_coeff > 0 if not equality else None
340
+ strict = prop.function in [Q.gt, Q.lt]
341
+ b = Boundary(var_to_lra_var[var], -const, upper, equality, strict)
342
+ encoding[enc] = b
343
+
344
+ fs = [v.free_symbols for v in nonbasic + basic]
345
+ assert all(len(syms) > 0 for syms in fs)
346
+ fs_count = sum(len(syms) for syms in fs)
347
+ if len(fs) > 0 and len(set.union(*fs)) < fs_count:
348
+ raise UnhandledInput("Nonlinearity is not handled")
349
+
350
+ A, _ = linear_eq_to_matrix(A, nonbasic + basic)
351
+ nonbasic = [var_to_lra_var[nb] for nb in nonbasic]
352
+ basic = [var_to_lra_var[b] for b in basic]
353
+ for idx, var in enumerate(nonbasic + basic):
354
+ var.col_idx = idx
355
+
356
+ return LRASolver(A, basic, nonbasic, encoding, s_subs, testing_mode), conflicts
357
+
358
+ def reset_bounds(self):
359
+ """
360
+ Resets the state of the LRASolver to before
361
+ anything was asserted.
362
+ """
363
+ self.result = None
364
+ for var in self.all_var:
365
+ var.lower = LRARational(-float("inf"), 0)
366
+ var.lower_from_eq = False
367
+ var.lower_from_neg = False
368
+ var.upper = LRARational(float("inf"), 0)
369
+ var.upper_from_eq= False
370
+ var.lower_from_neg = False
371
+ var.assign = LRARational(0, 0)
372
+
373
+ def assert_lit(self, enc_constraint):
374
+ """
375
+ Assert a literal representing a constraint
376
+ and update the internal state accordingly.
377
+
378
+ Note that due to peculiarities of this implementation
379
+ asserting ~(x > 0) will assert (x <= 0) but asserting
380
+ ~Eq(x, 0) will not do anything.
381
+
382
+ Parameters
383
+ ==========
384
+
385
+ enc_constraint : int
386
+ A mapping of encodings to constraints
387
+ can be found in `self.enc_to_boundary`.
388
+
389
+ Returns
390
+ =======
391
+
392
+ None or (False, explanation)
393
+
394
+ explanation : set of ints
395
+ A conflict clause that "explains" why
396
+ the literals asserted so far are unsatisfiable.
397
+ """
398
+ if abs(enc_constraint) not in self.enc_to_boundary:
399
+ return None
400
+
401
+ if not HANDLE_NEGATION and enc_constraint < 0:
402
+ return None
403
+
404
+ boundary = self.enc_to_boundary[abs(enc_constraint)]
405
+ sym, c, negated = boundary.var, boundary.bound, enc_constraint < 0
406
+
407
+ if boundary.equality and negated:
408
+ return None # negated equality is not handled and should only appear in conflict clauses
409
+
410
+ upper = boundary.upper != negated
411
+ if boundary.strict != negated:
412
+ delta = -1 if upper else 1
413
+ c = LRARational(c, delta)
414
+ else:
415
+ c = LRARational(c, 0)
416
+
417
+ if boundary.equality:
418
+ res1 = self._assert_lower(sym, c, from_equality=True, from_neg=negated)
419
+ if res1 and res1[0] == False:
420
+ res = res1
421
+ else:
422
+ res2 = self._assert_upper(sym, c, from_equality=True, from_neg=negated)
423
+ res = res2
424
+ elif upper:
425
+ res = self._assert_upper(sym, c, from_neg=negated)
426
+ else:
427
+ res = self._assert_lower(sym, c, from_neg=negated)
428
+
429
+ if self.is_sat and sym not in self.slack_set:
430
+ self.is_sat = res is None
431
+ else:
432
+ self.is_sat = False
433
+
434
+ return res
435
+
436
+ def _assert_upper(self, xi, ci, from_equality=False, from_neg=False):
437
+ """
438
+ Adjusts the upper bound on variable xi if the new upper bound is
439
+ more limiting. The assignment of variable xi is adjusted to be
440
+ within the new bound if needed.
441
+
442
+ Also calls `self._update` to update the assignment for slack variables
443
+ to keep all equalities satisfied.
444
+ """
445
+ if self.result:
446
+ assert self.result[0] != False
447
+ self.result = None
448
+ if ci >= xi.upper:
449
+ return None
450
+ if ci < xi.lower:
451
+ assert (xi.lower[1] >= 0) is True
452
+ assert (ci[1] <= 0) is True
453
+
454
+ lit1, neg1 = Boundary.from_lower(xi)
455
+
456
+ lit2 = Boundary(var=xi, const=ci[0], strict=ci[1] != 0, upper=True, equality=from_equality)
457
+ if from_neg:
458
+ lit2 = lit2.get_negated()
459
+ neg2 = -1 if from_neg else 1
460
+
461
+ conflict = [-neg1*self.boundary_to_enc[lit1], -neg2*self.boundary_to_enc[lit2]]
462
+ self.result = False, conflict
463
+ return self.result
464
+ xi.upper = ci
465
+ xi.upper_from_eq = from_equality
466
+ xi.upper_from_neg = from_neg
467
+ if xi in self.nonslack and xi.assign > ci:
468
+ self._update(xi, ci)
469
+
470
+ if self.run_checks and all(v.assign[0] != float("inf") and v.assign[0] != -float("inf")
471
+ for v in self.all_var):
472
+ M = self.A
473
+ X = Matrix([v.assign[0] for v in self.all_var])
474
+ assert all(abs(val) < 10 ** (-10) for val in M * X)
475
+
476
+ return None
477
+
478
+ def _assert_lower(self, xi, ci, from_equality=False, from_neg=False):
479
+ """
480
+ Adjusts the lower bound on variable xi if the new lower bound is
481
+ more limiting. The assignment of variable xi is adjusted to be
482
+ within the new bound if needed.
483
+
484
+ Also calls `self._update` to update the assignment for slack variables
485
+ to keep all equalities satisfied.
486
+ """
487
+ if self.result:
488
+ assert self.result[0] != False
489
+ self.result = None
490
+ if ci <= xi.lower:
491
+ return None
492
+ if ci > xi.upper:
493
+ assert (xi.upper[1] <= 0) is True
494
+ assert (ci[1] >= 0) is True
495
+
496
+ lit1, neg1 = Boundary.from_upper(xi)
497
+
498
+ lit2 = Boundary(var=xi, const=ci[0], strict=ci[1] != 0, upper=False, equality=from_equality)
499
+ if from_neg:
500
+ lit2 = lit2.get_negated()
501
+ neg2 = -1 if from_neg else 1
502
+
503
+ conflict = [-neg1*self.boundary_to_enc[lit1],-neg2*self.boundary_to_enc[lit2]]
504
+ self.result = False, conflict
505
+ return self.result
506
+ xi.lower = ci
507
+ xi.lower_from_eq = from_equality
508
+ xi.lower_from_neg = from_neg
509
+ if xi in self.nonslack and xi.assign < ci:
510
+ self._update(xi, ci)
511
+
512
+ if self.run_checks and all(v.assign[0] != float("inf") and v.assign[0] != -float("inf")
513
+ for v in self.all_var):
514
+ M = self.A
515
+ X = Matrix([v.assign[0] for v in self.all_var])
516
+ assert all(abs(val) < 10 ** (-10) for val in M * X)
517
+
518
+ return None
519
+
520
+ def _update(self, xi, v):
521
+ """
522
+ Updates all slack variables that have equations that contain
523
+ variable xi so that they stay satisfied given xi is equal to v.
524
+ """
525
+ i = xi.col_idx
526
+ for j, b in enumerate(self.slack):
527
+ aji = self.A[j, i]
528
+ b.assign = b.assign + (v - xi.assign)*aji
529
+ xi.assign = v
530
+
531
+ def check(self):
532
+ """
533
+ Searches for an assignment that satisfies all constraints
534
+ or determines that no such assignment exists and gives
535
+ a minimal conflict clause that "explains" why the
536
+ constraints are unsatisfiable.
537
+
538
+ Returns
539
+ =======
540
+
541
+ (True, assignment) or (False, explanation)
542
+
543
+ assignment : dict of LRAVariables to values
544
+ Assigned values are tuples that represent a rational number
545
+ plus some infinatesimal delta.
546
+
547
+ explanation : set of ints
548
+ """
549
+ if self.is_sat:
550
+ return True, {var: var.assign for var in self.all_var}
551
+ if self.result:
552
+ return self.result
553
+
554
+ from sympy.matrices.dense import Matrix
555
+ M = self.A.copy()
556
+ basic = {s: i for i, s in enumerate(self.slack)} # contains the row index associated with each basic variable
557
+ nonbasic = set(self.nonslack)
558
+ iteration = 0
559
+ while True:
560
+ iteration += 1
561
+
562
+ if self.run_checks:
563
+ # nonbasic variables must always be within bounds
564
+ assert all(((nb.assign >= nb.lower) == True) and ((nb.assign <= nb.upper) == True) for nb in nonbasic)
565
+
566
+ # assignments for x must always satisfy Ax = 0
567
+ # probably have to turn this off when dealing with strict ineq
568
+ if all(v.assign[0] != float("inf") and v.assign[0] != -float("inf")
569
+ for v in self.all_var):
570
+ X = Matrix([v.assign[0] for v in self.all_var])
571
+ assert all(abs(val) < 10**(-10) for val in M*X)
572
+
573
+ # check upper and lower match this format:
574
+ # x <= rat + delta iff x < rat
575
+ # x >= rat - delta iff x > rat
576
+ # this wouldn't make sense:
577
+ # x <= rat - delta
578
+ # x >= rat + delta
579
+ assert all(x.upper[1] <= 0 for x in self.all_var)
580
+ assert all(x.lower[1] >= 0 for x in self.all_var)
581
+
582
+ cand = [b for b in basic if b.assign < b.lower or b.assign > b.upper]
583
+
584
+ if len(cand) == 0:
585
+ return True, {var: var.assign for var in self.all_var}
586
+
587
+ xi = min(cand, key=lambda v: v.col_idx) # Bland's rule
588
+ i = basic[xi]
589
+
590
+ if xi.assign < xi.lower:
591
+ cand = [nb for nb in nonbasic
592
+ if (M[i, nb.col_idx] > 0 and nb.assign < nb.upper)
593
+ or (M[i, nb.col_idx] < 0 and nb.assign > nb.lower)]
594
+ if len(cand) == 0:
595
+ N_plus = [nb for nb in nonbasic if M[i, nb.col_idx] > 0]
596
+ N_minus = [nb for nb in nonbasic if M[i, nb.col_idx] < 0]
597
+
598
+ conflict = []
599
+ conflict += [Boundary.from_upper(nb) for nb in N_plus]
600
+ conflict += [Boundary.from_lower(nb) for nb in N_minus]
601
+ conflict.append(Boundary.from_lower(xi))
602
+ conflict = [-neg*self.boundary_to_enc[c] for c, neg in conflict]
603
+ return False, conflict
604
+ xj = min(cand, key=str)
605
+ M = self._pivot_and_update(M, basic, nonbasic, xi, xj, xi.lower)
606
+
607
+ if xi.assign > xi.upper:
608
+ cand = [nb for nb in nonbasic
609
+ if (M[i, nb.col_idx] < 0 and nb.assign < nb.upper)
610
+ or (M[i, nb.col_idx] > 0 and nb.assign > nb.lower)]
611
+
612
+ if len(cand) == 0:
613
+ N_plus = [nb for nb in nonbasic if M[i, nb.col_idx] > 0]
614
+ N_minus = [nb for nb in nonbasic if M[i, nb.col_idx] < 0]
615
+
616
+ conflict = []
617
+ conflict += [Boundary.from_upper(nb) for nb in N_minus]
618
+ conflict += [Boundary.from_lower(nb) for nb in N_plus]
619
+ conflict.append(Boundary.from_upper(xi))
620
+
621
+ conflict = [-neg*self.boundary_to_enc[c] for c, neg in conflict]
622
+ return False, conflict
623
+ xj = min(cand, key=lambda v: v.col_idx)
624
+ M = self._pivot_and_update(M, basic, nonbasic, xi, xj, xi.upper)
625
+
626
+ def _pivot_and_update(self, M, basic, nonbasic, xi, xj, v):
627
+ """
628
+ Pivots basic variable xi with nonbasic variable xj,
629
+ and sets value of xi to v and adjusts the values of all basic variables
630
+ to keep equations satisfied.
631
+ """
632
+ i, j = basic[xi], xj.col_idx
633
+ assert M[i, j] != 0
634
+ theta = (v - xi.assign)*(1/M[i, j])
635
+ xi.assign = v
636
+ xj.assign = xj.assign + theta
637
+ for xk in basic:
638
+ if xk != xi:
639
+ k = basic[xk]
640
+ akj = M[k, j]
641
+ xk.assign = xk.assign + theta*akj
642
+ # pivot
643
+ basic[xj] = basic[xi]
644
+ del basic[xi]
645
+ nonbasic.add(xi)
646
+ nonbasic.remove(xj)
647
+ return self._pivot(M, i, j)
648
+
649
+ @staticmethod
650
+ def _pivot(M, i, j):
651
+ """
652
+ Performs a pivot operation about entry i, j of M by performing
653
+ a series of row operations on a copy of M and returing the result.
654
+ The original M is left unmodified.
655
+
656
+ Conceptually, M represents a system of equations and pivoting
657
+ can be thought of as rearranging equation i to be in terms of
658
+ variable j and then substituting in the rest of the equations
659
+ to get rid of other occurances of variable j.
660
+
661
+ Example
662
+ =======
663
+
664
+ >>> from sympy.matrices.dense import Matrix
665
+ >>> from sympy.logic.algorithms.lra_theory import LRASolver
666
+ >>> from sympy import var
667
+ >>> Matrix(3, 3, var('a:i'))
668
+ Matrix([
669
+ [a, b, c],
670
+ [d, e, f],
671
+ [g, h, i]])
672
+
673
+ This matrix is equivalent to:
674
+ 0 = a*x + b*y + c*z
675
+ 0 = d*x + e*y + f*z
676
+ 0 = g*x + h*y + i*z
677
+
678
+ >>> LRASolver._pivot(_, 1, 0)
679
+ Matrix([
680
+ [ 0, -a*e/d + b, -a*f/d + c],
681
+ [-1, -e/d, -f/d],
682
+ [ 0, h - e*g/d, i - f*g/d]])
683
+
684
+ We rearrange equation 1 in terms of variable 0 (x)
685
+ and substitute to remove x from the other equations.
686
+
687
+ 0 = 0 + (-a*e/d + b)*y + (-a*f/d + c)*z
688
+ 0 = -x + (-e/d)*y + (-f/d)*z
689
+ 0 = 0 + (h - e*g/d)*y + (i - f*g/d)*z
690
+ """
691
+ _, _, Mij = M[i, :], M[:, j], M[i, j]
692
+ if Mij == 0:
693
+ raise ZeroDivisionError("Tried to pivot about zero-valued entry.")
694
+ A = M.copy()
695
+ A[i, :] = -A[i, :]/Mij
696
+ for row in range(M.shape[0]):
697
+ if row != i:
698
+ A[row, :] = A[row, :] + A[row, j] * A[i, :]
699
+
700
+ return A
701
+
702
+
703
+ def _sep_const_coeff(expr):
704
+ """
705
+ Example
706
+ =======
707
+
708
+ >>> from sympy.logic.algorithms.lra_theory import _sep_const_coeff
709
+ >>> from sympy.abc import x, y
710
+ >>> _sep_const_coeff(2*x)
711
+ (x, 2)
712
+ >>> _sep_const_coeff(2*x + 3*y)
713
+ (2*x + 3*y, 1)
714
+ """
715
+ if isinstance(expr, Add):
716
+ return expr, sympify(1)
717
+
718
+ if isinstance(expr, Mul):
719
+ coeffs = expr.args
720
+ else:
721
+ coeffs = [expr]
722
+
723
+ var, const = [], []
724
+ for c in coeffs:
725
+ c = sympify(c)
726
+ if len(c.free_symbols)==0:
727
+ const.append(c)
728
+ else:
729
+ var.append(c)
730
+ return Mul(*var), Mul(*const)
731
+
732
+
733
+ def _list_terms(expr):
734
+ if not isinstance(expr, Add):
735
+ return [expr]
736
+
737
+ return expr.args
738
+
739
+
740
+ def _sep_const_terms(expr):
741
+ """
742
+ Example
743
+ =======
744
+
745
+ >>> from sympy.logic.algorithms.lra_theory import _sep_const_terms
746
+ >>> from sympy.abc import x, y
747
+ >>> _sep_const_terms(2*x + 3*y + 2)
748
+ (2*x + 3*y, 2)
749
+ """
750
+ if isinstance(expr, Add):
751
+ terms = expr.args
752
+ else:
753
+ terms = [expr]
754
+
755
+ var, const = [], []
756
+ for t in terms:
757
+ if len(t.free_symbols) == 0:
758
+ const.append(t)
759
+ else:
760
+ var.append(t)
761
+ return sum(var), sum(const)
762
+
763
+
764
+ def _eval_binrel(binrel):
765
+ """
766
+ Simplify binary relation to True / False if possible.
767
+ """
768
+ if not (len(binrel.lhs.free_symbols) == 0 and len(binrel.rhs.free_symbols) == 0):
769
+ return binrel
770
+ if binrel.function == Q.lt:
771
+ res = binrel.lhs < binrel.rhs
772
+ elif binrel.function == Q.gt:
773
+ res = binrel.lhs > binrel.rhs
774
+ elif binrel.function == Q.le:
775
+ res = binrel.lhs <= binrel.rhs
776
+ elif binrel.function == Q.ge:
777
+ res = binrel.lhs >= binrel.rhs
778
+ elif binrel.function == Q.eq:
779
+ res = Eq(binrel.lhs, binrel.rhs)
780
+ elif binrel.function == Q.ne:
781
+ res = Ne(binrel.lhs, binrel.rhs)
782
+
783
+ if res == True or res == False:
784
+ return res
785
+ else:
786
+ return None
787
+
788
+
789
+ class Boundary:
790
+ """
791
+ Represents an upper or lower bound or an equality between a symbol
792
+ and some constant.
793
+ """
794
+ def __init__(self, var, const, upper, equality, strict=None):
795
+ if not equality in [True, False]:
796
+ assert equality in [True, False]
797
+
798
+
799
+ self.var = var
800
+ if isinstance(const, tuple):
801
+ s = const[1] != 0
802
+ if strict:
803
+ assert s == strict
804
+ self.bound = const[0]
805
+ self.strict = s
806
+ else:
807
+ self.bound = const
808
+ self.strict = strict
809
+ self.upper = upper if not equality else None
810
+ self.equality = equality
811
+ self.strict = strict
812
+ assert self.strict is not None
813
+
814
+ @staticmethod
815
+ def from_upper(var):
816
+ neg = -1 if var.upper_from_neg else 1
817
+ b = Boundary(var, var.upper[0], True, var.upper_from_eq, var.upper[1] != 0)
818
+ if neg < 0:
819
+ b = b.get_negated()
820
+ return b, neg
821
+
822
+ @staticmethod
823
+ def from_lower(var):
824
+ neg = -1 if var.lower_from_neg else 1
825
+ b = Boundary(var, var.lower[0], False, var.lower_from_eq, var.lower[1] != 0)
826
+ if neg < 0:
827
+ b = b.get_negated()
828
+ return b, neg
829
+
830
+ def get_negated(self):
831
+ return Boundary(self.var, self.bound, not self.upper, self.equality, not self.strict)
832
+
833
+ def get_inequality(self):
834
+ if self.equality:
835
+ return Eq(self.var.var, self.bound)
836
+ elif self.upper and self.strict:
837
+ return self.var.var < self.bound
838
+ elif not self.upper and self.strict:
839
+ return self.var.var > self.bound
840
+ elif self.upper:
841
+ return self.var.var <= self.bound
842
+ else:
843
+ return self.var.var >= self.bound
844
+
845
+ def __repr__(self):
846
+ return repr("Boundry(" + repr(self.get_inequality()) + ")")
847
+
848
+ def __eq__(self, other):
849
+ other = (other.var, other.bound, other.strict, other.upper, other.equality)
850
+ return (self.var, self.bound, self.strict, self.upper, self.equality) == other
851
+
852
+ def __hash__(self):
853
+ return hash((self.var, self.bound, self.strict, self.upper, self.equality))
854
+
855
+
856
+ class LRARational():
857
+ """
858
+ Represents a rational plus or minus some amount
859
+ of arbitrary small deltas.
860
+ """
861
+ def __init__(self, rational, delta):
862
+ self.value = (rational, delta)
863
+
864
+ def __lt__(self, other):
865
+ return self.value < other.value
866
+
867
+ def __le__(self, other):
868
+ return self.value <= other.value
869
+
870
+ def __eq__(self, other):
871
+ return self.value == other.value
872
+
873
+ def __add__(self, other):
874
+ return LRARational(self.value[0] + other.value[0], self.value[1] + other.value[1])
875
+
876
+ def __sub__(self, other):
877
+ return LRARational(self.value[0] - other.value[0], self.value[1] - other.value[1])
878
+
879
+ def __mul__(self, other):
880
+ assert not isinstance(other, LRARational)
881
+ return LRARational(self.value[0] * other, self.value[1] * other)
882
+
883
+ def __getitem__(self, index):
884
+ return self.value[index]
885
+
886
+ def __repr__(self):
887
+ return repr(self.value)
888
+
889
+
890
+ class LRAVariable():
891
+ """
892
+ Object to keep track of upper and lower bounds
893
+ on `self.var`.
894
+ """
895
+ def __init__(self, var):
896
+ self.upper = LRARational(float("inf"), 0)
897
+ self.upper_from_eq = False
898
+ self.upper_from_neg = False
899
+ self.lower = LRARational(-float("inf"), 0)
900
+ self.lower_from_eq = False
901
+ self.lower_from_neg = False
902
+ self.assign = LRARational(0,0)
903
+ self.var = var
904
+ self.col_idx = None
905
+
906
+ def __repr__(self):
907
+ return repr(self.var)
908
+
909
+ def __eq__(self, other):
910
+ if not isinstance(other, LRAVariable):
911
+ return False
912
+ return other.var == self.var
913
+
914
+ def __hash__(self):
915
+ return hash(self.var)
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/minisat22_wrapper.py ADDED
@@ -0,0 +1,46 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ from sympy.assumptions.cnf import EncodedCNF
2
+
3
+ def minisat22_satisfiable(expr, all_models=False, minimal=False):
4
+
5
+ if not isinstance(expr, EncodedCNF):
6
+ exprs = EncodedCNF()
7
+ exprs.add_prop(expr)
8
+ expr = exprs
9
+
10
+ from pysat.solvers import Minisat22
11
+
12
+ # Return UNSAT when False (encoded as 0) is present in the CNF
13
+ if {0} in expr.data:
14
+ if all_models:
15
+ return (f for f in [False])
16
+ return False
17
+
18
+ r = Minisat22(expr.data)
19
+
20
+ if minimal:
21
+ r.set_phases([-(i+1) for i in range(r.nof_vars())])
22
+
23
+ if not r.solve():
24
+ return False
25
+
26
+ if not all_models:
27
+ return {expr.symbols[abs(lit) - 1]: lit > 0 for lit in r.get_model()}
28
+
29
+ else:
30
+ # Make solutions SymPy compatible by creating a generator
31
+ def _gen(results):
32
+ satisfiable = False
33
+ while results.solve():
34
+ sol = results.get_model()
35
+ yield {expr.symbols[abs(lit) - 1]: lit > 0 for lit in sol}
36
+ if minimal:
37
+ results.add_clause([-i for i in sol if i>0])
38
+ else:
39
+ results.add_clause([-i for i in sol])
40
+ satisfiable = True
41
+ if not satisfiable:
42
+ yield False
43
+ raise StopIteration
44
+
45
+
46
+ return _gen(r)
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/pycosat_wrapper.py ADDED
@@ -0,0 +1,41 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ from sympy.assumptions.cnf import EncodedCNF
2
+
3
+
4
+ def pycosat_satisfiable(expr, all_models=False):
5
+ import pycosat
6
+ if not isinstance(expr, EncodedCNF):
7
+ exprs = EncodedCNF()
8
+ exprs.add_prop(expr)
9
+ expr = exprs
10
+
11
+ # Return UNSAT when False (encoded as 0) is present in the CNF
12
+ if {0} in expr.data:
13
+ if all_models:
14
+ return (f for f in [False])
15
+ return False
16
+
17
+ if not all_models:
18
+ r = pycosat.solve(expr.data)
19
+ result = (r != "UNSAT")
20
+ if not result:
21
+ return result
22
+ return {expr.symbols[abs(lit) - 1]: lit > 0 for lit in r}
23
+ else:
24
+ r = pycosat.itersolve(expr.data)
25
+ result = (r != "UNSAT")
26
+ if not result:
27
+ return result
28
+
29
+ # Make solutions SymPy compatible by creating a generator
30
+ def _gen(results):
31
+ satisfiable = False
32
+ try:
33
+ while True:
34
+ sol = next(results)
35
+ yield {expr.symbols[abs(lit) - 1]: lit > 0 for lit in sol}
36
+ satisfiable = True
37
+ except StopIteration:
38
+ if not satisfiable:
39
+ yield False
40
+
41
+ return _gen(r)
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/algorithms/z3_wrapper.py ADDED
@@ -0,0 +1,115 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ from sympy.printing.smtlib import smtlib_code
2
+ from sympy.assumptions.assume import AppliedPredicate
3
+ from sympy.assumptions.cnf import EncodedCNF
4
+ from sympy.assumptions.ask import Q
5
+
6
+ from sympy.core import Add, Mul
7
+ from sympy.core.relational import Equality, LessThan, GreaterThan, StrictLessThan, StrictGreaterThan
8
+ from sympy.functions.elementary.complexes import Abs
9
+ from sympy.functions.elementary.exponential import Pow
10
+ from sympy.functions.elementary.miscellaneous import Min, Max
11
+ from sympy.logic.boolalg import And, Or, Xor, Implies
12
+ from sympy.logic.boolalg import Not, ITE
13
+ from sympy.assumptions.relation.equality import StrictGreaterThanPredicate, StrictLessThanPredicate, GreaterThanPredicate, LessThanPredicate, EqualityPredicate
14
+ from sympy.external import import_module
15
+
16
+ def z3_satisfiable(expr, all_models=False):
17
+ if not isinstance(expr, EncodedCNF):
18
+ exprs = EncodedCNF()
19
+ exprs.add_prop(expr)
20
+ expr = exprs
21
+
22
+ z3 = import_module("z3")
23
+ if z3 is None:
24
+ raise ImportError("z3 is not installed")
25
+
26
+ s = encoded_cnf_to_z3_solver(expr, z3)
27
+
28
+ res = str(s.check())
29
+ if res == "unsat":
30
+ return False
31
+ elif res == "sat":
32
+ return z3_model_to_sympy_model(s.model(), expr)
33
+ else:
34
+ return None
35
+
36
+
37
+ def z3_model_to_sympy_model(z3_model, enc_cnf):
38
+ rev_enc = {value : key for key, value in enc_cnf.encoding.items()}
39
+ return {rev_enc[int(var.name()[1:])] : bool(z3_model[var]) for var in z3_model}
40
+
41
+
42
+ def clause_to_assertion(clause):
43
+ clause_strings = [f"d{abs(lit)}" if lit > 0 else f"(not d{abs(lit)})" for lit in clause]
44
+ return "(assert (or " + " ".join(clause_strings) + "))"
45
+
46
+
47
+ def encoded_cnf_to_z3_solver(enc_cnf, z3):
48
+ def dummify_bool(pred):
49
+ return False
50
+ assert isinstance(pred, AppliedPredicate)
51
+
52
+ if pred.function in [Q.positive, Q.negative, Q.zero]:
53
+ return pred
54
+ else:
55
+ return False
56
+
57
+ s = z3.Solver()
58
+
59
+ declarations = [f"(declare-const d{var} Bool)" for var in enc_cnf.variables]
60
+ assertions = [clause_to_assertion(clause) for clause in enc_cnf.data]
61
+
62
+ symbols = set()
63
+ for pred, enc in enc_cnf.encoding.items():
64
+ if not isinstance(pred, AppliedPredicate):
65
+ continue
66
+ if pred.function not in (Q.gt, Q.lt, Q.ge, Q.le, Q.ne, Q.eq, Q.positive, Q.negative, Q.extended_negative, Q.extended_positive, Q.zero, Q.nonzero, Q.nonnegative, Q.nonpositive, Q.extended_nonzero, Q.extended_nonnegative, Q.extended_nonpositive):
67
+ continue
68
+
69
+ pred_str = smtlib_code(pred, auto_declare=False, auto_assert=False, known_functions=known_functions)
70
+
71
+ symbols |= pred.free_symbols
72
+ pred = pred_str
73
+ clause = f"(implies d{enc} {pred})"
74
+ assertion = "(assert " + clause + ")"
75
+ assertions.append(assertion)
76
+
77
+ for sym in symbols:
78
+ declarations.append(f"(declare-const {sym} Real)")
79
+
80
+ declarations = "\n".join(declarations)
81
+ assertions = "\n".join(assertions)
82
+ s.from_string(declarations)
83
+ s.from_string(assertions)
84
+
85
+ return s
86
+
87
+
88
+ known_functions = {
89
+ Add: '+',
90
+ Mul: '*',
91
+
92
+ Equality: '=',
93
+ LessThan: '<=',
94
+ GreaterThan: '>=',
95
+ StrictLessThan: '<',
96
+ StrictGreaterThan: '>',
97
+
98
+ EqualityPredicate(): '=',
99
+ LessThanPredicate(): '<=',
100
+ GreaterThanPredicate(): '>=',
101
+ StrictLessThanPredicate(): '<',
102
+ StrictGreaterThanPredicate(): '>',
103
+
104
+ Abs: 'abs',
105
+ Min: 'min',
106
+ Max: 'max',
107
+ Pow: '^',
108
+
109
+ And: 'and',
110
+ Or: 'or',
111
+ Xor: 'xor',
112
+ Not: 'not',
113
+ ITE: 'ite',
114
+ Implies: '=>',
115
+ }
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/boolalg.py ADDED
The diff for this file is too large to render. See raw diff
 
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/inference.py ADDED
@@ -0,0 +1,340 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """Inference in propositional logic"""
2
+
3
+ from sympy.logic.boolalg import And, Not, conjuncts, to_cnf, BooleanFunction
4
+ from sympy.core.sorting import ordered
5
+ from sympy.core.sympify import sympify
6
+ from sympy.external.importtools import import_module
7
+
8
+
9
+ def literal_symbol(literal):
10
+ """
11
+ The symbol in this literal (without the negation).
12
+
13
+ Examples
14
+ ========
15
+
16
+ >>> from sympy.abc import A
17
+ >>> from sympy.logic.inference import literal_symbol
18
+ >>> literal_symbol(A)
19
+ A
20
+ >>> literal_symbol(~A)
21
+ A
22
+
23
+ """
24
+
25
+ if literal is True or literal is False:
26
+ return literal
27
+ elif literal.is_Symbol:
28
+ return literal
29
+ elif literal.is_Not:
30
+ return literal_symbol(literal.args[0])
31
+ else:
32
+ raise ValueError("Argument must be a boolean literal.")
33
+
34
+
35
+ def satisfiable(expr, algorithm=None, all_models=False, minimal=False, use_lra_theory=False):
36
+ """
37
+ Check satisfiability of a propositional sentence.
38
+ Returns a model when it succeeds.
39
+ Returns {true: true} for trivially true expressions.
40
+
41
+ On setting all_models to True, if given expr is satisfiable then
42
+ returns a generator of models. However, if expr is unsatisfiable
43
+ then returns a generator containing the single element False.
44
+
45
+ Examples
46
+ ========
47
+
48
+ >>> from sympy.abc import A, B
49
+ >>> from sympy.logic.inference import satisfiable
50
+ >>> satisfiable(A & ~B)
51
+ {A: True, B: False}
52
+ >>> satisfiable(A & ~A)
53
+ False
54
+ >>> satisfiable(True)
55
+ {True: True}
56
+ >>> next(satisfiable(A & ~A, all_models=True))
57
+ False
58
+ >>> models = satisfiable((A >> B) & B, all_models=True)
59
+ >>> next(models)
60
+ {A: False, B: True}
61
+ >>> next(models)
62
+ {A: True, B: True}
63
+ >>> def use_models(models):
64
+ ... for model in models:
65
+ ... if model:
66
+ ... # Do something with the model.
67
+ ... print(model)
68
+ ... else:
69
+ ... # Given expr is unsatisfiable.
70
+ ... print("UNSAT")
71
+ >>> use_models(satisfiable(A >> ~A, all_models=True))
72
+ {A: False}
73
+ >>> use_models(satisfiable(A ^ A, all_models=True))
74
+ UNSAT
75
+
76
+ """
77
+ if use_lra_theory:
78
+ if algorithm is not None and algorithm != "dpll2":
79
+ raise ValueError(f"Currently only dpll2 can handle using lra theory. {algorithm} is not handled.")
80
+ algorithm = "dpll2"
81
+
82
+ if algorithm is None or algorithm == "pycosat":
83
+ pycosat = import_module('pycosat')
84
+ if pycosat is not None:
85
+ algorithm = "pycosat"
86
+ else:
87
+ if algorithm == "pycosat":
88
+ raise ImportError("pycosat module is not present")
89
+ # Silently fall back to dpll2 if pycosat
90
+ # is not installed
91
+ algorithm = "dpll2"
92
+
93
+ if algorithm=="minisat22":
94
+ pysat = import_module('pysat')
95
+ if pysat is None:
96
+ algorithm = "dpll2"
97
+
98
+ if algorithm=="z3":
99
+ z3 = import_module('z3')
100
+ if z3 is None:
101
+ algorithm = "dpll2"
102
+
103
+ if algorithm == "dpll":
104
+ from sympy.logic.algorithms.dpll import dpll_satisfiable
105
+ return dpll_satisfiable(expr)
106
+ elif algorithm == "dpll2":
107
+ from sympy.logic.algorithms.dpll2 import dpll_satisfiable
108
+ return dpll_satisfiable(expr, all_models, use_lra_theory=use_lra_theory)
109
+ elif algorithm == "pycosat":
110
+ from sympy.logic.algorithms.pycosat_wrapper import pycosat_satisfiable
111
+ return pycosat_satisfiable(expr, all_models)
112
+ elif algorithm == "minisat22":
113
+ from sympy.logic.algorithms.minisat22_wrapper import minisat22_satisfiable
114
+ return minisat22_satisfiable(expr, all_models, minimal)
115
+ elif algorithm == "z3":
116
+ from sympy.logic.algorithms.z3_wrapper import z3_satisfiable
117
+ return z3_satisfiable(expr, all_models)
118
+
119
+ raise NotImplementedError
120
+
121
+
122
+ def valid(expr):
123
+ """
124
+ Check validity of a propositional sentence.
125
+ A valid propositional sentence is True under every assignment.
126
+
127
+ Examples
128
+ ========
129
+
130
+ >>> from sympy.abc import A, B
131
+ >>> from sympy.logic.inference import valid
132
+ >>> valid(A | ~A)
133
+ True
134
+ >>> valid(A | B)
135
+ False
136
+
137
+ References
138
+ ==========
139
+
140
+ .. [1] https://en.wikipedia.org/wiki/Validity
141
+
142
+ """
143
+ return not satisfiable(Not(expr))
144
+
145
+
146
+ def pl_true(expr, model=None, deep=False):
147
+ """
148
+ Returns whether the given assignment is a model or not.
149
+
150
+ If the assignment does not specify the value for every proposition,
151
+ this may return None to indicate 'not obvious'.
152
+
153
+ Parameters
154
+ ==========
155
+
156
+ model : dict, optional, default: {}
157
+ Mapping of symbols to boolean values to indicate assignment.
158
+ deep: boolean, optional, default: False
159
+ Gives the value of the expression under partial assignments
160
+ correctly. May still return None to indicate 'not obvious'.
161
+
162
+
163
+ Examples
164
+ ========
165
+
166
+ >>> from sympy.abc import A, B
167
+ >>> from sympy.logic.inference import pl_true
168
+ >>> pl_true( A & B, {A: True, B: True})
169
+ True
170
+ >>> pl_true(A & B, {A: False})
171
+ False
172
+ >>> pl_true(A & B, {A: True})
173
+ >>> pl_true(A & B, {A: True}, deep=True)
174
+ >>> pl_true(A >> (B >> A))
175
+ >>> pl_true(A >> (B >> A), deep=True)
176
+ True
177
+ >>> pl_true(A & ~A)
178
+ >>> pl_true(A & ~A, deep=True)
179
+ False
180
+ >>> pl_true(A & B & (~A | ~B), {A: True})
181
+ >>> pl_true(A & B & (~A | ~B), {A: True}, deep=True)
182
+ False
183
+
184
+ """
185
+
186
+ from sympy.core.symbol import Symbol
187
+
188
+ boolean = (True, False)
189
+
190
+ def _validate(expr):
191
+ if isinstance(expr, Symbol) or expr in boolean:
192
+ return True
193
+ if not isinstance(expr, BooleanFunction):
194
+ return False
195
+ return all(_validate(arg) for arg in expr.args)
196
+
197
+ if expr in boolean:
198
+ return expr
199
+ expr = sympify(expr)
200
+ if not _validate(expr):
201
+ raise ValueError("%s is not a valid boolean expression" % expr)
202
+ if not model:
203
+ model = {}
204
+ model = {k: v for k, v in model.items() if v in boolean}
205
+ result = expr.subs(model)
206
+ if result in boolean:
207
+ return bool(result)
208
+ if deep:
209
+ model = dict.fromkeys(result.atoms(), True)
210
+ if pl_true(result, model):
211
+ if valid(result):
212
+ return True
213
+ else:
214
+ if not satisfiable(result):
215
+ return False
216
+ return None
217
+
218
+
219
+ def entails(expr, formula_set=None):
220
+ """
221
+ Check whether the given expr_set entail an expr.
222
+ If formula_set is empty then it returns the validity of expr.
223
+
224
+ Examples
225
+ ========
226
+
227
+ >>> from sympy.abc import A, B, C
228
+ >>> from sympy.logic.inference import entails
229
+ >>> entails(A, [A >> B, B >> C])
230
+ False
231
+ >>> entails(C, [A >> B, B >> C, A])
232
+ True
233
+ >>> entails(A >> B)
234
+ False
235
+ >>> entails(A >> (B >> A))
236
+ True
237
+
238
+ References
239
+ ==========
240
+
241
+ .. [1] https://en.wikipedia.org/wiki/Logical_consequence
242
+
243
+ """
244
+ if formula_set:
245
+ formula_set = list(formula_set)
246
+ else:
247
+ formula_set = []
248
+ formula_set.append(Not(expr))
249
+ return not satisfiable(And(*formula_set))
250
+
251
+
252
+ class KB:
253
+ """Base class for all knowledge bases"""
254
+ def __init__(self, sentence=None):
255
+ self.clauses_ = set()
256
+ if sentence:
257
+ self.tell(sentence)
258
+
259
+ def tell(self, sentence):
260
+ raise NotImplementedError
261
+
262
+ def ask(self, query):
263
+ raise NotImplementedError
264
+
265
+ def retract(self, sentence):
266
+ raise NotImplementedError
267
+
268
+ @property
269
+ def clauses(self):
270
+ return list(ordered(self.clauses_))
271
+
272
+
273
+ class PropKB(KB):
274
+ """A KB for Propositional Logic. Inefficient, with no indexing."""
275
+
276
+ def tell(self, sentence):
277
+ """Add the sentence's clauses to the KB
278
+
279
+ Examples
280
+ ========
281
+
282
+ >>> from sympy.logic.inference import PropKB
283
+ >>> from sympy.abc import x, y
284
+ >>> l = PropKB()
285
+ >>> l.clauses
286
+ []
287
+
288
+ >>> l.tell(x | y)
289
+ >>> l.clauses
290
+ [x | y]
291
+
292
+ >>> l.tell(y)
293
+ >>> l.clauses
294
+ [y, x | y]
295
+
296
+ """
297
+ for c in conjuncts(to_cnf(sentence)):
298
+ self.clauses_.add(c)
299
+
300
+ def ask(self, query):
301
+ """Checks if the query is true given the set of clauses.
302
+
303
+ Examples
304
+ ========
305
+
306
+ >>> from sympy.logic.inference import PropKB
307
+ >>> from sympy.abc import x, y
308
+ >>> l = PropKB()
309
+ >>> l.tell(x & ~y)
310
+ >>> l.ask(x)
311
+ True
312
+ >>> l.ask(y)
313
+ False
314
+
315
+ """
316
+ return entails(query, self.clauses_)
317
+
318
+ def retract(self, sentence):
319
+ """Remove the sentence's clauses from the KB
320
+
321
+ Examples
322
+ ========
323
+
324
+ >>> from sympy.logic.inference import PropKB
325
+ >>> from sympy.abc import x, y
326
+ >>> l = PropKB()
327
+ >>> l.clauses
328
+ []
329
+
330
+ >>> l.tell(x | y)
331
+ >>> l.clauses
332
+ [x | y]
333
+
334
+ >>> l.retract(x | y)
335
+ >>> l.clauses
336
+ []
337
+
338
+ """
339
+ for c in conjuncts(to_cnf(sentence)):
340
+ self.clauses_.discard(c)
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/tests/__pycache__/__init__.cpython-310.pyc ADDED
Binary file (179 Bytes). View file
 
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/tests/__pycache__/test_boolalg.cpython-310.pyc ADDED
Binary file (49 kB). View file
 
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/utilities/__init__.py ADDED
@@ -0,0 +1,3 @@
 
 
 
 
1
+ from .dimacs import load_file
2
+
3
+ __all__ = ['load_file']
evalkit_internvl/lib/python3.10/site-packages/sympy/logic/utilities/__pycache__/__init__.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/utilities/__pycache__/dimacs.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/logic/utilities/dimacs.py ADDED
@@ -0,0 +1,70 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """For reading in DIMACS file format
2
+
3
+ www.cs.ubc.ca/~hoos/SATLIB/Benchmarks/SAT/satformat.ps
4
+
5
+ """
6
+
7
+ from sympy.core import Symbol
8
+ from sympy.logic.boolalg import And, Or
9
+ import re
10
+
11
+
12
+ def load(s):
13
+ """Loads a boolean expression from a string.
14
+
15
+ Examples
16
+ ========
17
+
18
+ >>> from sympy.logic.utilities.dimacs import load
19
+ >>> load('1')
20
+ cnf_1
21
+ >>> load('1 2')
22
+ cnf_1 | cnf_2
23
+ >>> load('1 \\n 2')
24
+ cnf_1 & cnf_2
25
+ >>> load('1 2 \\n 3')
26
+ cnf_3 & (cnf_1 | cnf_2)
27
+ """
28
+ clauses = []
29
+
30
+ lines = s.split('\n')
31
+
32
+ pComment = re.compile(r'c.*')
33
+ pStats = re.compile(r'p\s*cnf\s*(\d*)\s*(\d*)')
34
+
35
+ while len(lines) > 0:
36
+ line = lines.pop(0)
37
+
38
+ # Only deal with lines that aren't comments
39
+ if not pComment.match(line):
40
+ m = pStats.match(line)
41
+
42
+ if not m:
43
+ nums = line.rstrip('\n').split(' ')
44
+ list = []
45
+ for lit in nums:
46
+ if lit != '':
47
+ if int(lit) == 0:
48
+ continue
49
+ num = abs(int(lit))
50
+ sign = True
51
+ if int(lit) < 0:
52
+ sign = False
53
+
54
+ if sign:
55
+ list.append(Symbol("cnf_%s" % num))
56
+ else:
57
+ list.append(~Symbol("cnf_%s" % num))
58
+
59
+ if len(list) > 0:
60
+ clauses.append(Or(*list))
61
+
62
+ return And(*clauses)
63
+
64
+
65
+ def load_file(location):
66
+ """Loads a boolean expression from a file."""
67
+ with open(location) as f:
68
+ s = f.read()
69
+
70
+ return load(s)
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/experimental_lambdify.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/plot.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/plotgrid.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/series.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/__pycache__/textplot.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__init__.py ADDED
@@ -0,0 +1,12 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ from .interval_arithmetic import interval
2
+ from .lib_interval import (Abs, exp, log, log10, sin, cos, tan, sqrt,
3
+ imin, imax, sinh, cosh, tanh, acosh, asinh, atanh,
4
+ asin, acos, atan, ceil, floor, And, Or)
5
+
6
+ __all__ = [
7
+ 'interval',
8
+
9
+ 'Abs', 'exp', 'log', 'log10', 'sin', 'cos', 'tan', 'sqrt', 'imin', 'imax',
10
+ 'sinh', 'cosh', 'tanh', 'acosh', 'asinh', 'atanh', 'asin', 'acos', 'atan',
11
+ 'ceil', 'floor', 'And', 'Or',
12
+ ]
evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__pycache__/__init__.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__pycache__/interval_arithmetic.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__pycache__/interval_membership.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/__pycache__/lib_interval.cpython-310.pyc ADDED
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evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/lib_interval.py ADDED
@@ -0,0 +1,452 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """ The module contains implemented functions for interval arithmetic."""
2
+ from functools import reduce
3
+
4
+ from sympy.plotting.intervalmath import interval
5
+ from sympy.external import import_module
6
+
7
+
8
+ def Abs(x):
9
+ if isinstance(x, (int, float)):
10
+ return interval(abs(x))
11
+ elif isinstance(x, interval):
12
+ if x.start < 0 and x.end > 0:
13
+ return interval(0, max(abs(x.start), abs(x.end)), is_valid=x.is_valid)
14
+ else:
15
+ return interval(abs(x.start), abs(x.end))
16
+ else:
17
+ raise NotImplementedError
18
+
19
+ #Monotonic
20
+
21
+
22
+ def exp(x):
23
+ """evaluates the exponential of an interval"""
24
+ np = import_module('numpy')
25
+ if isinstance(x, (int, float)):
26
+ return interval(np.exp(x), np.exp(x))
27
+ elif isinstance(x, interval):
28
+ return interval(np.exp(x.start), np.exp(x.end), is_valid=x.is_valid)
29
+ else:
30
+ raise NotImplementedError
31
+
32
+
33
+ #Monotonic
34
+ def log(x):
35
+ """evaluates the natural logarithm of an interval"""
36
+ np = import_module('numpy')
37
+ if isinstance(x, (int, float)):
38
+ if x <= 0:
39
+ return interval(-np.inf, np.inf, is_valid=False)
40
+ else:
41
+ return interval(np.log(x))
42
+ elif isinstance(x, interval):
43
+ if not x.is_valid:
44
+ return interval(-np.inf, np.inf, is_valid=x.is_valid)
45
+ elif x.end <= 0:
46
+ return interval(-np.inf, np.inf, is_valid=False)
47
+ elif x.start <= 0:
48
+ return interval(-np.inf, np.inf, is_valid=None)
49
+
50
+ return interval(np.log(x.start), np.log(x.end))
51
+ else:
52
+ raise NotImplementedError
53
+
54
+
55
+ #Monotonic
56
+ def log10(x):
57
+ """evaluates the logarithm to the base 10 of an interval"""
58
+ np = import_module('numpy')
59
+ if isinstance(x, (int, float)):
60
+ if x <= 0:
61
+ return interval(-np.inf, np.inf, is_valid=False)
62
+ else:
63
+ return interval(np.log10(x))
64
+ elif isinstance(x, interval):
65
+ if not x.is_valid:
66
+ return interval(-np.inf, np.inf, is_valid=x.is_valid)
67
+ elif x.end <= 0:
68
+ return interval(-np.inf, np.inf, is_valid=False)
69
+ elif x.start <= 0:
70
+ return interval(-np.inf, np.inf, is_valid=None)
71
+ return interval(np.log10(x.start), np.log10(x.end))
72
+ else:
73
+ raise NotImplementedError
74
+
75
+
76
+ #Monotonic
77
+ def atan(x):
78
+ """evaluates the tan inverse of an interval"""
79
+ np = import_module('numpy')
80
+ if isinstance(x, (int, float)):
81
+ return interval(np.arctan(x))
82
+ elif isinstance(x, interval):
83
+ start = np.arctan(x.start)
84
+ end = np.arctan(x.end)
85
+ return interval(start, end, is_valid=x.is_valid)
86
+ else:
87
+ raise NotImplementedError
88
+
89
+
90
+ #periodic
91
+ def sin(x):
92
+ """evaluates the sine of an interval"""
93
+ np = import_module('numpy')
94
+ if isinstance(x, (int, float)):
95
+ return interval(np.sin(x))
96
+ elif isinstance(x, interval):
97
+ if not x.is_valid:
98
+ return interval(-1, 1, is_valid=x.is_valid)
99
+ na, __ = divmod(x.start, np.pi / 2.0)
100
+ nb, __ = divmod(x.end, np.pi / 2.0)
101
+ start = min(np.sin(x.start), np.sin(x.end))
102
+ end = max(np.sin(x.start), np.sin(x.end))
103
+ if nb - na > 4:
104
+ return interval(-1, 1, is_valid=x.is_valid)
105
+ elif na == nb:
106
+ return interval(start, end, is_valid=x.is_valid)
107
+ else:
108
+ if (na - 1) // 4 != (nb - 1) // 4:
109
+ #sin has max
110
+ end = 1
111
+ if (na - 3) // 4 != (nb - 3) // 4:
112
+ #sin has min
113
+ start = -1
114
+ return interval(start, end)
115
+ else:
116
+ raise NotImplementedError
117
+
118
+
119
+ #periodic
120
+ def cos(x):
121
+ """Evaluates the cos of an interval"""
122
+ np = import_module('numpy')
123
+ if isinstance(x, (int, float)):
124
+ return interval(np.sin(x))
125
+ elif isinstance(x, interval):
126
+ if not (np.isfinite(x.start) and np.isfinite(x.end)):
127
+ return interval(-1, 1, is_valid=x.is_valid)
128
+ na, __ = divmod(x.start, np.pi / 2.0)
129
+ nb, __ = divmod(x.end, np.pi / 2.0)
130
+ start = min(np.cos(x.start), np.cos(x.end))
131
+ end = max(np.cos(x.start), np.cos(x.end))
132
+ if nb - na > 4:
133
+ #differ more than 2*pi
134
+ return interval(-1, 1, is_valid=x.is_valid)
135
+ elif na == nb:
136
+ #in the same quadarant
137
+ return interval(start, end, is_valid=x.is_valid)
138
+ else:
139
+ if (na) // 4 != (nb) // 4:
140
+ #cos has max
141
+ end = 1
142
+ if (na - 2) // 4 != (nb - 2) // 4:
143
+ #cos has min
144
+ start = -1
145
+ return interval(start, end, is_valid=x.is_valid)
146
+ else:
147
+ raise NotImplementedError
148
+
149
+
150
+ def tan(x):
151
+ """Evaluates the tan of an interval"""
152
+ return sin(x) / cos(x)
153
+
154
+
155
+ #Monotonic
156
+ def sqrt(x):
157
+ """Evaluates the square root of an interval"""
158
+ np = import_module('numpy')
159
+ if isinstance(x, (int, float)):
160
+ if x > 0:
161
+ return interval(np.sqrt(x))
162
+ else:
163
+ return interval(-np.inf, np.inf, is_valid=False)
164
+ elif isinstance(x, interval):
165
+ #Outside the domain
166
+ if x.end < 0:
167
+ return interval(-np.inf, np.inf, is_valid=False)
168
+ #Partially outside the domain
169
+ elif x.start < 0:
170
+ return interval(-np.inf, np.inf, is_valid=None)
171
+ else:
172
+ return interval(np.sqrt(x.start), np.sqrt(x.end),
173
+ is_valid=x.is_valid)
174
+ else:
175
+ raise NotImplementedError
176
+
177
+
178
+ def imin(*args):
179
+ """Evaluates the minimum of a list of intervals"""
180
+ np = import_module('numpy')
181
+ if not all(isinstance(arg, (int, float, interval)) for arg in args):
182
+ return NotImplementedError
183
+ else:
184
+ new_args = [a for a in args if isinstance(a, (int, float))
185
+ or a.is_valid]
186
+ if len(new_args) == 0:
187
+ if all(a.is_valid is False for a in args):
188
+ return interval(-np.inf, np.inf, is_valid=False)
189
+ else:
190
+ return interval(-np.inf, np.inf, is_valid=None)
191
+ start_array = [a if isinstance(a, (int, float)) else a.start
192
+ for a in new_args]
193
+
194
+ end_array = [a if isinstance(a, (int, float)) else a.end
195
+ for a in new_args]
196
+ return interval(min(start_array), min(end_array))
197
+
198
+
199
+ def imax(*args):
200
+ """Evaluates the maximum of a list of intervals"""
201
+ np = import_module('numpy')
202
+ if not all(isinstance(arg, (int, float, interval)) for arg in args):
203
+ return NotImplementedError
204
+ else:
205
+ new_args = [a for a in args if isinstance(a, (int, float))
206
+ or a.is_valid]
207
+ if len(new_args) == 0:
208
+ if all(a.is_valid is False for a in args):
209
+ return interval(-np.inf, np.inf, is_valid=False)
210
+ else:
211
+ return interval(-np.inf, np.inf, is_valid=None)
212
+ start_array = [a if isinstance(a, (int, float)) else a.start
213
+ for a in new_args]
214
+
215
+ end_array = [a if isinstance(a, (int, float)) else a.end
216
+ for a in new_args]
217
+
218
+ return interval(max(start_array), max(end_array))
219
+
220
+
221
+ #Monotonic
222
+ def sinh(x):
223
+ """Evaluates the hyperbolic sine of an interval"""
224
+ np = import_module('numpy')
225
+ if isinstance(x, (int, float)):
226
+ return interval(np.sinh(x), np.sinh(x))
227
+ elif isinstance(x, interval):
228
+ return interval(np.sinh(x.start), np.sinh(x.end), is_valid=x.is_valid)
229
+ else:
230
+ raise NotImplementedError
231
+
232
+
233
+ def cosh(x):
234
+ """Evaluates the hyperbolic cos of an interval"""
235
+ np = import_module('numpy')
236
+ if isinstance(x, (int, float)):
237
+ return interval(np.cosh(x), np.cosh(x))
238
+ elif isinstance(x, interval):
239
+ #both signs
240
+ if x.start < 0 and x.end > 0:
241
+ end = max(np.cosh(x.start), np.cosh(x.end))
242
+ return interval(1, end, is_valid=x.is_valid)
243
+ else:
244
+ #Monotonic
245
+ start = np.cosh(x.start)
246
+ end = np.cosh(x.end)
247
+ return interval(start, end, is_valid=x.is_valid)
248
+ else:
249
+ raise NotImplementedError
250
+
251
+
252
+ #Monotonic
253
+ def tanh(x):
254
+ """Evaluates the hyperbolic tan of an interval"""
255
+ np = import_module('numpy')
256
+ if isinstance(x, (int, float)):
257
+ return interval(np.tanh(x), np.tanh(x))
258
+ elif isinstance(x, interval):
259
+ return interval(np.tanh(x.start), np.tanh(x.end), is_valid=x.is_valid)
260
+ else:
261
+ raise NotImplementedError
262
+
263
+
264
+ def asin(x):
265
+ """Evaluates the inverse sine of an interval"""
266
+ np = import_module('numpy')
267
+ if isinstance(x, (int, float)):
268
+ #Outside the domain
269
+ if abs(x) > 1:
270
+ return interval(-np.inf, np.inf, is_valid=False)
271
+ else:
272
+ return interval(np.arcsin(x), np.arcsin(x))
273
+ elif isinstance(x, interval):
274
+ #Outside the domain
275
+ if x.is_valid is False or x.start > 1 or x.end < -1:
276
+ return interval(-np.inf, np.inf, is_valid=False)
277
+ #Partially outside the domain
278
+ elif x.start < -1 or x.end > 1:
279
+ return interval(-np.inf, np.inf, is_valid=None)
280
+ else:
281
+ start = np.arcsin(x.start)
282
+ end = np.arcsin(x.end)
283
+ return interval(start, end, is_valid=x.is_valid)
284
+
285
+
286
+ def acos(x):
287
+ """Evaluates the inverse cos of an interval"""
288
+ np = import_module('numpy')
289
+ if isinstance(x, (int, float)):
290
+ if abs(x) > 1:
291
+ #Outside the domain
292
+ return interval(-np.inf, np.inf, is_valid=False)
293
+ else:
294
+ return interval(np.arccos(x), np.arccos(x))
295
+ elif isinstance(x, interval):
296
+ #Outside the domain
297
+ if x.is_valid is False or x.start > 1 or x.end < -1:
298
+ return interval(-np.inf, np.inf, is_valid=False)
299
+ #Partially outside the domain
300
+ elif x.start < -1 or x.end > 1:
301
+ return interval(-np.inf, np.inf, is_valid=None)
302
+ else:
303
+ start = np.arccos(x.start)
304
+ end = np.arccos(x.end)
305
+ return interval(start, end, is_valid=x.is_valid)
306
+
307
+
308
+ def ceil(x):
309
+ """Evaluates the ceiling of an interval"""
310
+ np = import_module('numpy')
311
+ if isinstance(x, (int, float)):
312
+ return interval(np.ceil(x))
313
+ elif isinstance(x, interval):
314
+ if x.is_valid is False:
315
+ return interval(-np.inf, np.inf, is_valid=False)
316
+ else:
317
+ start = np.ceil(x.start)
318
+ end = np.ceil(x.end)
319
+ #Continuous over the interval
320
+ if start == end:
321
+ return interval(start, end, is_valid=x.is_valid)
322
+ else:
323
+ #Not continuous over the interval
324
+ return interval(start, end, is_valid=None)
325
+ else:
326
+ return NotImplementedError
327
+
328
+
329
+ def floor(x):
330
+ """Evaluates the floor of an interval"""
331
+ np = import_module('numpy')
332
+ if isinstance(x, (int, float)):
333
+ return interval(np.floor(x))
334
+ elif isinstance(x, interval):
335
+ if x.is_valid is False:
336
+ return interval(-np.inf, np.inf, is_valid=False)
337
+ else:
338
+ start = np.floor(x.start)
339
+ end = np.floor(x.end)
340
+ #continuous over the argument
341
+ if start == end:
342
+ return interval(start, end, is_valid=x.is_valid)
343
+ else:
344
+ #not continuous over the interval
345
+ return interval(start, end, is_valid=None)
346
+ else:
347
+ return NotImplementedError
348
+
349
+
350
+ def acosh(x):
351
+ """Evaluates the inverse hyperbolic cosine of an interval"""
352
+ np = import_module('numpy')
353
+ if isinstance(x, (int, float)):
354
+ #Outside the domain
355
+ if x < 1:
356
+ return interval(-np.inf, np.inf, is_valid=False)
357
+ else:
358
+ return interval(np.arccosh(x))
359
+ elif isinstance(x, interval):
360
+ #Outside the domain
361
+ if x.end < 1:
362
+ return interval(-np.inf, np.inf, is_valid=False)
363
+ #Partly outside the domain
364
+ elif x.start < 1:
365
+ return interval(-np.inf, np.inf, is_valid=None)
366
+ else:
367
+ start = np.arccosh(x.start)
368
+ end = np.arccosh(x.end)
369
+ return interval(start, end, is_valid=x.is_valid)
370
+ else:
371
+ return NotImplementedError
372
+
373
+
374
+ #Monotonic
375
+ def asinh(x):
376
+ """Evaluates the inverse hyperbolic sine of an interval"""
377
+ np = import_module('numpy')
378
+ if isinstance(x, (int, float)):
379
+ return interval(np.arcsinh(x))
380
+ elif isinstance(x, interval):
381
+ start = np.arcsinh(x.start)
382
+ end = np.arcsinh(x.end)
383
+ return interval(start, end, is_valid=x.is_valid)
384
+ else:
385
+ return NotImplementedError
386
+
387
+
388
+ def atanh(x):
389
+ """Evaluates the inverse hyperbolic tangent of an interval"""
390
+ np = import_module('numpy')
391
+ if isinstance(x, (int, float)):
392
+ #Outside the domain
393
+ if abs(x) >= 1:
394
+ return interval(-np.inf, np.inf, is_valid=False)
395
+ else:
396
+ return interval(np.arctanh(x))
397
+ elif isinstance(x, interval):
398
+ #outside the domain
399
+ if x.is_valid is False or x.start >= 1 or x.end <= -1:
400
+ return interval(-np.inf, np.inf, is_valid=False)
401
+ #partly outside the domain
402
+ elif x.start <= -1 or x.end >= 1:
403
+ return interval(-np.inf, np.inf, is_valid=None)
404
+ else:
405
+ start = np.arctanh(x.start)
406
+ end = np.arctanh(x.end)
407
+ return interval(start, end, is_valid=x.is_valid)
408
+ else:
409
+ return NotImplementedError
410
+
411
+
412
+ #Three valued logic for interval plotting.
413
+
414
+ def And(*args):
415
+ """Defines the three valued ``And`` behaviour for a 2-tuple of
416
+ three valued logic values"""
417
+ def reduce_and(cmp_intervala, cmp_intervalb):
418
+ if cmp_intervala[0] is False or cmp_intervalb[0] is False:
419
+ first = False
420
+ elif cmp_intervala[0] is None or cmp_intervalb[0] is None:
421
+ first = None
422
+ else:
423
+ first = True
424
+ if cmp_intervala[1] is False or cmp_intervalb[1] is False:
425
+ second = False
426
+ elif cmp_intervala[1] is None or cmp_intervalb[1] is None:
427
+ second = None
428
+ else:
429
+ second = True
430
+ return (first, second)
431
+ return reduce(reduce_and, args)
432
+
433
+
434
+ def Or(*args):
435
+ """Defines the three valued ``Or`` behaviour for a 2-tuple of
436
+ three valued logic values"""
437
+ def reduce_or(cmp_intervala, cmp_intervalb):
438
+ if cmp_intervala[0] is True or cmp_intervalb[0] is True:
439
+ first = True
440
+ elif cmp_intervala[0] is None or cmp_intervalb[0] is None:
441
+ first = None
442
+ else:
443
+ first = False
444
+
445
+ if cmp_intervala[1] is True or cmp_intervalb[1] is True:
446
+ second = True
447
+ elif cmp_intervala[1] is None or cmp_intervalb[1] is None:
448
+ second = None
449
+ else:
450
+ second = False
451
+ return (first, second)
452
+ return reduce(reduce_or, args)
evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/intervalmath/tests/__pycache__/test_interval_functions.cpython-310.pyc ADDED
Binary file (9.29 kB). View file
 
evalkit_internvl/lib/python3.10/site-packages/sympy/plotting/tests/__pycache__/test_series.cpython-310.pyc ADDED
Binary file (49.2 kB). View file
 
evalkit_internvl/lib/python3.10/site-packages/sympy/series/__init__.py ADDED
@@ -0,0 +1,23 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """A module that handles series: find a limit, order the series etc.
2
+ """
3
+ from .order import Order
4
+ from .limits import limit, Limit
5
+ from .gruntz import gruntz
6
+ from .series import series
7
+ from .approximants import approximants
8
+ from .residues import residue
9
+ from .sequences import SeqPer, SeqFormula, sequence, SeqAdd, SeqMul
10
+ from .fourier import fourier_series
11
+ from .formal import fps
12
+ from .limitseq import difference_delta, limit_seq
13
+
14
+ from sympy.core.singleton import S
15
+ EmptySequence = S.EmptySequence
16
+
17
+ O = Order
18
+
19
+ __all__ = ['Order', 'O', 'limit', 'Limit', 'gruntz', 'series', 'approximants',
20
+ 'residue', 'EmptySequence', 'SeqPer', 'SeqFormula', 'sequence',
21
+ 'SeqAdd', 'SeqMul', 'fourier_series', 'fps', 'difference_delta',
22
+ 'limit_seq'
23
+ ]
evalkit_internvl/lib/python3.10/site-packages/sympy/series/acceleration.py ADDED
@@ -0,0 +1,101 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """
2
+ Convergence acceleration / extrapolation methods for series and
3
+ sequences.
4
+
5
+ References:
6
+ Carl M. Bender & Steven A. Orszag, "Advanced Mathematical Methods for
7
+ Scientists and Engineers: Asymptotic Methods and Perturbation Theory",
8
+ Springer 1999. (Shanks transformation: pp. 368-375, Richardson
9
+ extrapolation: pp. 375-377.)
10
+ """
11
+
12
+ from sympy.core.numbers import Integer
13
+ from sympy.core.singleton import S
14
+ from sympy.functions.combinatorial.factorials import factorial
15
+
16
+
17
+ def richardson(A, k, n, N):
18
+ """
19
+ Calculate an approximation for lim k->oo A(k) using Richardson
20
+ extrapolation with the terms A(n), A(n+1), ..., A(n+N+1).
21
+ Choosing N ~= 2*n often gives good results.
22
+
23
+ Examples
24
+ ========
25
+
26
+ A simple example is to calculate exp(1) using the limit definition.
27
+ This limit converges slowly; n = 100 only produces two accurate
28
+ digits:
29
+
30
+ >>> from sympy.abc import n
31
+ >>> e = (1 + 1/n)**n
32
+ >>> print(round(e.subs(n, 100).evalf(), 10))
33
+ 2.7048138294
34
+
35
+ Richardson extrapolation with 11 appropriately chosen terms gives
36
+ a value that is accurate to the indicated precision:
37
+
38
+ >>> from sympy import E
39
+ >>> from sympy.series.acceleration import richardson
40
+ >>> print(round(richardson(e, n, 10, 20).evalf(), 10))
41
+ 2.7182818285
42
+ >>> print(round(E.evalf(), 10))
43
+ 2.7182818285
44
+
45
+ Another useful application is to speed up convergence of series.
46
+ Computing 100 terms of the zeta(2) series 1/k**2 yields only
47
+ two accurate digits:
48
+
49
+ >>> from sympy.abc import k, n
50
+ >>> from sympy import Sum
51
+ >>> A = Sum(k**-2, (k, 1, n))
52
+ >>> print(round(A.subs(n, 100).evalf(), 10))
53
+ 1.6349839002
54
+
55
+ Richardson extrapolation performs much better:
56
+
57
+ >>> from sympy import pi
58
+ >>> print(round(richardson(A, n, 10, 20).evalf(), 10))
59
+ 1.6449340668
60
+ >>> print(round(((pi**2)/6).evalf(), 10)) # Exact value
61
+ 1.6449340668
62
+
63
+ """
64
+ s = S.Zero
65
+ for j in range(0, N + 1):
66
+ s += (A.subs(k, Integer(n + j)).doit() * (n + j)**N *
67
+ S.NegativeOne**(j + N) / (factorial(j) * factorial(N - j)))
68
+ return s
69
+
70
+
71
+ def shanks(A, k, n, m=1):
72
+ """
73
+ Calculate an approximation for lim k->oo A(k) using the n-term Shanks
74
+ transformation S(A)(n). With m > 1, calculate the m-fold recursive
75
+ Shanks transformation S(S(...S(A)...))(n).
76
+
77
+ The Shanks transformation is useful for summing Taylor series that
78
+ converge slowly near a pole or singularity, e.g. for log(2):
79
+
80
+ >>> from sympy.abc import k, n
81
+ >>> from sympy import Sum, Integer
82
+ >>> from sympy.series.acceleration import shanks
83
+ >>> A = Sum(Integer(-1)**(k+1) / k, (k, 1, n))
84
+ >>> print(round(A.subs(n, 100).doit().evalf(), 10))
85
+ 0.6881721793
86
+ >>> print(round(shanks(A, n, 25).evalf(), 10))
87
+ 0.6931396564
88
+ >>> print(round(shanks(A, n, 25, 5).evalf(), 10))
89
+ 0.6931471806
90
+
91
+ The correct value is 0.6931471805599453094172321215.
92
+ """
93
+ table = [A.subs(k, Integer(j)).doit() for j in range(n + m + 2)]
94
+ table2 = table[:]
95
+
96
+ for i in range(1, m + 1):
97
+ for j in range(i, n + m + 1):
98
+ x, y, z = table[j - 1], table[j], table[j + 1]
99
+ table2[j] = (z*x - y**2) / (z + x - 2*y)
100
+ table = table2[:]
101
+ return table[n]
evalkit_internvl/lib/python3.10/site-packages/sympy/series/approximants.py ADDED
@@ -0,0 +1,103 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ from sympy.core.singleton import S
2
+ from sympy.core.symbol import Symbol
3
+ from sympy.polys.polytools import lcm
4
+ from sympy.utilities import public
5
+
6
+ @public
7
+ def approximants(l, X=Symbol('x'), simplify=False):
8
+ """
9
+ Return a generator for consecutive Pade approximants for a series.
10
+ It can also be used for computing the rational generating function of a
11
+ series when possible, since the last approximant returned by the generator
12
+ will be the generating function (if any).
13
+
14
+ Explanation
15
+ ===========
16
+
17
+ The input list can contain more complex expressions than integer or rational
18
+ numbers; symbols may also be involved in the computation. An example below
19
+ show how to compute the generating function of the whole Pascal triangle.
20
+
21
+ The generator can be asked to apply the sympy.simplify function on each
22
+ generated term, which will make the computation slower; however it may be
23
+ useful when symbols are involved in the expressions.
24
+
25
+ Examples
26
+ ========
27
+
28
+ >>> from sympy.series import approximants
29
+ >>> from sympy import lucas, fibonacci, symbols, binomial
30
+ >>> g = [lucas(k) for k in range(16)]
31
+ >>> [e for e in approximants(g)]
32
+ [2, -4/(x - 2), (5*x - 2)/(3*x - 1), (x - 2)/(x**2 + x - 1)]
33
+
34
+ >>> h = [fibonacci(k) for k in range(16)]
35
+ >>> [e for e in approximants(h)]
36
+ [x, -x/(x - 1), (x**2 - x)/(2*x - 1), -x/(x**2 + x - 1)]
37
+
38
+ >>> x, t = symbols("x,t")
39
+ >>> p=[sum(binomial(k,i)*x**i for i in range(k+1)) for k in range(16)]
40
+ >>> y = approximants(p, t)
41
+ >>> for k in range(3): print(next(y))
42
+ 1
43
+ (x + 1)/((-x - 1)*(t*(x + 1) + (x + 1)/(-x - 1)))
44
+ nan
45
+
46
+ >>> y = approximants(p, t, simplify=True)
47
+ >>> for k in range(3): print(next(y))
48
+ 1
49
+ -1/(t*(x + 1) - 1)
50
+ nan
51
+
52
+ See Also
53
+ ========
54
+
55
+ sympy.concrete.guess.guess_generating_function_rational
56
+ mpmath.pade
57
+ """
58
+ from sympy.simplify import simplify as simp
59
+ from sympy.simplify.radsimp import denom
60
+ p1, q1 = [S.One], [S.Zero]
61
+ p2, q2 = [S.Zero], [S.One]
62
+ while len(l):
63
+ b = 0
64
+ while l[b]==0:
65
+ b += 1
66
+ if b == len(l):
67
+ return
68
+ m = [S.One/l[b]]
69
+ for k in range(b+1, len(l)):
70
+ s = 0
71
+ for j in range(b, k):
72
+ s -= l[j+1] * m[b-j-1]
73
+ m.append(s/l[b])
74
+ l = m
75
+ a, l[0] = l[0], 0
76
+ p = [0] * max(len(p2), b+len(p1))
77
+ q = [0] * max(len(q2), b+len(q1))
78
+ for k in range(len(p2)):
79
+ p[k] = a*p2[k]
80
+ for k in range(b, b+len(p1)):
81
+ p[k] += p1[k-b]
82
+ for k in range(len(q2)):
83
+ q[k] = a*q2[k]
84
+ for k in range(b, b+len(q1)):
85
+ q[k] += q1[k-b]
86
+ while p[-1]==0: p.pop()
87
+ while q[-1]==0: q.pop()
88
+ p1, p2 = p2, p
89
+ q1, q2 = q2, q
90
+
91
+ # yield result
92
+ c = 1
93
+ for x in p:
94
+ c = lcm(c, denom(x))
95
+ for x in q:
96
+ c = lcm(c, denom(x))
97
+ out = ( sum(c*e*X**k for k, e in enumerate(p))
98
+ / sum(c*e*X**k for k, e in enumerate(q)) )
99
+ if simplify:
100
+ yield(simp(out))
101
+ else:
102
+ yield out
103
+ return
evalkit_internvl/lib/python3.10/site-packages/sympy/series/aseries.py ADDED
@@ -0,0 +1,10 @@
 
 
 
 
 
 
 
 
 
 
 
1
+ from sympy.core.sympify import sympify
2
+
3
+
4
+ def aseries(expr, x=None, n=6, bound=0, hir=False):
5
+ """
6
+ See the docstring of Expr.aseries() for complete details of this wrapper.
7
+
8
+ """
9
+ expr = sympify(expr)
10
+ return expr.aseries(x, n, bound, hir)
evalkit_internvl/lib/python3.10/site-packages/sympy/series/formal.py ADDED
@@ -0,0 +1,1869 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """Formal Power Series"""
2
+
3
+ from collections import defaultdict
4
+
5
+ from sympy.core.numbers import (nan, oo, zoo)
6
+ from sympy.core.add import Add
7
+ from sympy.core.expr import Expr
8
+ from sympy.core.function import Derivative, Function, expand
9
+ from sympy.core.mul import Mul
10
+ from sympy.core.numbers import Rational
11
+ from sympy.core.relational import Eq
12
+ from sympy.sets.sets import Interval
13
+ from sympy.core.singleton import S
14
+ from sympy.core.symbol import Wild, Dummy, symbols, Symbol
15
+ from sympy.core.sympify import sympify
16
+ from sympy.discrete.convolutions import convolution
17
+ from sympy.functions.combinatorial.factorials import binomial, factorial, rf
18
+ from sympy.functions.combinatorial.numbers import bell
19
+ from sympy.functions.elementary.integers import floor, frac, ceiling
20
+ from sympy.functions.elementary.miscellaneous import Min, Max
21
+ from sympy.functions.elementary.piecewise import Piecewise
22
+ from sympy.series.limits import Limit
23
+ from sympy.series.order import Order
24
+ from sympy.series.sequences import sequence
25
+ from sympy.series.series_class import SeriesBase
26
+ from sympy.utilities.iterables import iterable
27
+
28
+
29
+
30
+ def rational_algorithm(f, x, k, order=4, full=False):
31
+ """
32
+ Rational algorithm for computing
33
+ formula of coefficients of Formal Power Series
34
+ of a function.
35
+
36
+ Explanation
37
+ ===========
38
+
39
+ Applicable when f(x) or some derivative of f(x)
40
+ is a rational function in x.
41
+
42
+ :func:`rational_algorithm` uses :func:`~.apart` function for partial fraction
43
+ decomposition. :func:`~.apart` by default uses 'undetermined coefficients
44
+ method'. By setting ``full=True``, 'Bronstein's algorithm' can be used
45
+ instead.
46
+
47
+ Looks for derivative of a function up to 4'th order (by default).
48
+ This can be overridden using order option.
49
+
50
+ Parameters
51
+ ==========
52
+
53
+ x : Symbol
54
+ order : int, optional
55
+ Order of the derivative of ``f``, Default is 4.
56
+ full : bool
57
+
58
+ Returns
59
+ =======
60
+
61
+ formula : Expr
62
+ ind : Expr
63
+ Independent terms.
64
+ order : int
65
+ full : bool
66
+
67
+ Examples
68
+ ========
69
+
70
+ >>> from sympy import log, atan
71
+ >>> from sympy.series.formal import rational_algorithm as ra
72
+ >>> from sympy.abc import x, k
73
+
74
+ >>> ra(1 / (1 - x), x, k)
75
+ (1, 0, 0)
76
+ >>> ra(log(1 + x), x, k)
77
+ (-1/((-1)**k*k), 0, 1)
78
+
79
+ >>> ra(atan(x), x, k, full=True)
80
+ ((-I/(2*(-I)**k) + I/(2*I**k))/k, 0, 1)
81
+
82
+ Notes
83
+ =====
84
+
85
+ By setting ``full=True``, range of admissible functions to be solved using
86
+ ``rational_algorithm`` can be increased. This option should be used
87
+ carefully as it can significantly slow down the computation as ``doit`` is
88
+ performed on the :class:`~.RootSum` object returned by the :func:`~.apart`
89
+ function. Use ``full=False`` whenever possible.
90
+
91
+ See Also
92
+ ========
93
+
94
+ sympy.polys.partfrac.apart
95
+
96
+ References
97
+ ==========
98
+
99
+ .. [1] Formal Power Series - Dominik Gruntz, Wolfram Koepf
100
+ .. [2] Power Series in Computer Algebra - Wolfram Koepf
101
+
102
+ """
103
+ from sympy.polys import RootSum, apart
104
+ from sympy.integrals import integrate
105
+
106
+ diff = f
107
+ ds = [] # list of diff
108
+
109
+ for i in range(order + 1):
110
+ if i:
111
+ diff = diff.diff(x)
112
+
113
+ if diff.is_rational_function(x):
114
+ coeff, sep = S.Zero, S.Zero
115
+
116
+ terms = apart(diff, x, full=full)
117
+ if terms.has(RootSum):
118
+ terms = terms.doit()
119
+
120
+ for t in Add.make_args(terms):
121
+ num, den = t.as_numer_denom()
122
+ if not den.has(x):
123
+ sep += t
124
+ else:
125
+ if isinstance(den, Mul):
126
+ # m*(n*x - a)**j -> (n*x - a)**j
127
+ ind = den.as_independent(x)
128
+ den = ind[1]
129
+ num /= ind[0]
130
+
131
+ # (n*x - a)**j -> (x - b)
132
+ den, j = den.as_base_exp()
133
+ a, xterm = den.as_coeff_add(x)
134
+
135
+ # term -> m/x**n
136
+ if not a:
137
+ sep += t
138
+ continue
139
+
140
+ xc = xterm[0].coeff(x)
141
+ a /= -xc
142
+ num /= xc**j
143
+
144
+ ak = ((-1)**j * num *
145
+ binomial(j + k - 1, k).rewrite(factorial) /
146
+ a**(j + k))
147
+ coeff += ak
148
+
149
+ # Hacky, better way?
150
+ if coeff.is_zero:
151
+ return None
152
+ if (coeff.has(x) or coeff.has(zoo) or coeff.has(oo) or
153
+ coeff.has(nan)):
154
+ return None
155
+
156
+ for j in range(i):
157
+ coeff = (coeff / (k + j + 1))
158
+ sep = integrate(sep, x)
159
+ sep += (ds.pop() - sep).limit(x, 0) # constant of integration
160
+ return (coeff.subs(k, k - i), sep, i)
161
+
162
+ else:
163
+ ds.append(diff)
164
+
165
+ return None
166
+
167
+
168
+ def rational_independent(terms, x):
169
+ """
170
+ Returns a list of all the rationally independent terms.
171
+
172
+ Examples
173
+ ========
174
+
175
+ >>> from sympy import sin, cos
176
+ >>> from sympy.series.formal import rational_independent
177
+ >>> from sympy.abc import x
178
+
179
+ >>> rational_independent([cos(x), sin(x)], x)
180
+ [cos(x), sin(x)]
181
+ >>> rational_independent([x**2, sin(x), x*sin(x), x**3], x)
182
+ [x**3 + x**2, x*sin(x) + sin(x)]
183
+ """
184
+ if not terms:
185
+ return []
186
+
187
+ ind = terms[0:1]
188
+
189
+ for t in terms[1:]:
190
+ n = t.as_independent(x)[1]
191
+ for i, term in enumerate(ind):
192
+ d = term.as_independent(x)[1]
193
+ q = (n / d).cancel()
194
+ if q.is_rational_function(x):
195
+ ind[i] += t
196
+ break
197
+ else:
198
+ ind.append(t)
199
+ return ind
200
+
201
+
202
+ def simpleDE(f, x, g, order=4):
203
+ r"""
204
+ Generates simple DE.
205
+
206
+ Explanation
207
+ ===========
208
+
209
+ DE is of the form
210
+
211
+ .. math::
212
+ f^k(x) + \sum\limits_{j=0}^{k-1} A_j f^j(x) = 0
213
+
214
+ where :math:`A_j` should be rational function in x.
215
+
216
+ Generates DE's upto order 4 (default). DE's can also have free parameters.
217
+
218
+ By increasing order, higher order DE's can be found.
219
+
220
+ Yields a tuple of (DE, order).
221
+ """
222
+ from sympy.solvers.solveset import linsolve
223
+
224
+ a = symbols('a:%d' % (order))
225
+
226
+ def _makeDE(k):
227
+ eq = f.diff(x, k) + Add(*[a[i]*f.diff(x, i) for i in range(0, k)])
228
+ DE = g(x).diff(x, k) + Add(*[a[i]*g(x).diff(x, i) for i in range(0, k)])
229
+ return eq, DE
230
+
231
+ found = False
232
+ for k in range(1, order + 1):
233
+ eq, DE = _makeDE(k)
234
+ eq = eq.expand()
235
+ terms = eq.as_ordered_terms()
236
+ ind = rational_independent(terms, x)
237
+ if found or len(ind) == k:
238
+ sol = dict(zip(a, (i for s in linsolve(ind, a[:k]) for i in s)))
239
+ if sol:
240
+ found = True
241
+ DE = DE.subs(sol)
242
+ DE = DE.as_numer_denom()[0]
243
+ DE = DE.factor().as_coeff_mul(Derivative)[1][0]
244
+ yield DE.collect(Derivative(g(x))), k
245
+
246
+
247
+ def exp_re(DE, r, k):
248
+ """Converts a DE with constant coefficients (explike) into a RE.
249
+
250
+ Explanation
251
+ ===========
252
+
253
+ Performs the substitution:
254
+
255
+ .. math::
256
+ f^j(x) \\to r(k + j)
257
+
258
+ Normalises the terms so that lowest order of a term is always r(k).
259
+
260
+ Examples
261
+ ========
262
+
263
+ >>> from sympy import Function, Derivative
264
+ >>> from sympy.series.formal import exp_re
265
+ >>> from sympy.abc import x, k
266
+ >>> f, r = Function('f'), Function('r')
267
+
268
+ >>> exp_re(-f(x) + Derivative(f(x)), r, k)
269
+ -r(k) + r(k + 1)
270
+ >>> exp_re(Derivative(f(x), x) + Derivative(f(x), (x, 2)), r, k)
271
+ r(k) + r(k + 1)
272
+
273
+ See Also
274
+ ========
275
+
276
+ sympy.series.formal.hyper_re
277
+ """
278
+ RE = S.Zero
279
+
280
+ g = DE.atoms(Function).pop()
281
+
282
+ mini = None
283
+ for t in Add.make_args(DE):
284
+ coeff, d = t.as_independent(g)
285
+ if isinstance(d, Derivative):
286
+ j = d.derivative_count
287
+ else:
288
+ j = 0
289
+ if mini is None or j < mini:
290
+ mini = j
291
+ RE += coeff * r(k + j)
292
+ if mini:
293
+ RE = RE.subs(k, k - mini)
294
+ return RE
295
+
296
+
297
+ def hyper_re(DE, r, k):
298
+ """
299
+ Converts a DE into a RE.
300
+
301
+ Explanation
302
+ ===========
303
+
304
+ Performs the substitution:
305
+
306
+ .. math::
307
+ x^l f^j(x) \\to (k + 1 - l)_j . a_{k + j - l}
308
+
309
+ Normalises the terms so that lowest order of a term is always r(k).
310
+
311
+ Examples
312
+ ========
313
+
314
+ >>> from sympy import Function, Derivative
315
+ >>> from sympy.series.formal import hyper_re
316
+ >>> from sympy.abc import x, k
317
+ >>> f, r = Function('f'), Function('r')
318
+
319
+ >>> hyper_re(-f(x) + Derivative(f(x)), r, k)
320
+ (k + 1)*r(k + 1) - r(k)
321
+ >>> hyper_re(-x*f(x) + Derivative(f(x), (x, 2)), r, k)
322
+ (k + 2)*(k + 3)*r(k + 3) - r(k)
323
+
324
+ See Also
325
+ ========
326
+
327
+ sympy.series.formal.exp_re
328
+ """
329
+ RE = S.Zero
330
+
331
+ g = DE.atoms(Function).pop()
332
+ x = g.atoms(Symbol).pop()
333
+
334
+ mini = None
335
+ for t in Add.make_args(DE.expand()):
336
+ coeff, d = t.as_independent(g)
337
+ c, v = coeff.as_independent(x)
338
+ l = v.as_coeff_exponent(x)[1]
339
+ if isinstance(d, Derivative):
340
+ j = d.derivative_count
341
+ else:
342
+ j = 0
343
+ RE += c * rf(k + 1 - l, j) * r(k + j - l)
344
+ if mini is None or j - l < mini:
345
+ mini = j - l
346
+
347
+ RE = RE.subs(k, k - mini)
348
+
349
+ m = Wild('m')
350
+ return RE.collect(r(k + m))
351
+
352
+
353
+ def _transformation_a(f, x, P, Q, k, m, shift):
354
+ f *= x**(-shift)
355
+ P = P.subs(k, k + shift)
356
+ Q = Q.subs(k, k + shift)
357
+ return f, P, Q, m
358
+
359
+
360
+ def _transformation_c(f, x, P, Q, k, m, scale):
361
+ f = f.subs(x, x**scale)
362
+ P = P.subs(k, k / scale)
363
+ Q = Q.subs(k, k / scale)
364
+ m *= scale
365
+ return f, P, Q, m
366
+
367
+
368
+ def _transformation_e(f, x, P, Q, k, m):
369
+ f = f.diff(x)
370
+ P = P.subs(k, k + 1) * (k + m + 1)
371
+ Q = Q.subs(k, k + 1) * (k + 1)
372
+ return f, P, Q, m
373
+
374
+
375
+ def _apply_shift(sol, shift):
376
+ return [(res, cond + shift) for res, cond in sol]
377
+
378
+
379
+ def _apply_scale(sol, scale):
380
+ return [(res, cond / scale) for res, cond in sol]
381
+
382
+
383
+ def _apply_integrate(sol, x, k):
384
+ return [(res / ((cond + 1)*(cond.as_coeff_Add()[1].coeff(k))), cond + 1)
385
+ for res, cond in sol]
386
+
387
+
388
+ def _compute_formula(f, x, P, Q, k, m, k_max):
389
+ """Computes the formula for f."""
390
+ from sympy.polys import roots
391
+
392
+ sol = []
393
+ for i in range(k_max + 1, k_max + m + 1):
394
+ if (i < 0) == True:
395
+ continue
396
+ r = f.diff(x, i).limit(x, 0) / factorial(i)
397
+ if r.is_zero:
398
+ continue
399
+
400
+ kterm = m*k + i
401
+ res = r
402
+
403
+ p = P.subs(k, kterm)
404
+ q = Q.subs(k, kterm)
405
+ c1 = p.subs(k, 1/k).leadterm(k)[0]
406
+ c2 = q.subs(k, 1/k).leadterm(k)[0]
407
+ res *= (-c1 / c2)**k
408
+
409
+ res *= Mul(*[rf(-r, k)**mul for r, mul in roots(p, k).items()])
410
+ res /= Mul(*[rf(-r, k)**mul for r, mul in roots(q, k).items()])
411
+
412
+ sol.append((res, kterm))
413
+
414
+ return sol
415
+
416
+
417
+ def _rsolve_hypergeometric(f, x, P, Q, k, m):
418
+ """
419
+ Recursive wrapper to rsolve_hypergeometric.
420
+
421
+ Explanation
422
+ ===========
423
+
424
+ Returns a Tuple of (formula, series independent terms,
425
+ maximum power of x in independent terms) if successful
426
+ otherwise ``None``.
427
+
428
+ See :func:`rsolve_hypergeometric` for details.
429
+ """
430
+ from sympy.polys import lcm, roots
431
+ from sympy.integrals import integrate
432
+
433
+ # transformation - c
434
+ proots, qroots = roots(P, k), roots(Q, k)
435
+ all_roots = dict(proots)
436
+ all_roots.update(qroots)
437
+ scale = lcm([r.as_numer_denom()[1] for r, t in all_roots.items()
438
+ if r.is_rational])
439
+ f, P, Q, m = _transformation_c(f, x, P, Q, k, m, scale)
440
+
441
+ # transformation - a
442
+ qroots = roots(Q, k)
443
+ if qroots:
444
+ k_min = Min(*qroots.keys())
445
+ else:
446
+ k_min = S.Zero
447
+ shift = k_min + m
448
+ f, P, Q, m = _transformation_a(f, x, P, Q, k, m, shift)
449
+
450
+ l = (x*f).limit(x, 0)
451
+ if not isinstance(l, Limit) and l != 0: # Ideally should only be l != 0
452
+ return None
453
+
454
+ qroots = roots(Q, k)
455
+ if qroots:
456
+ k_max = Max(*qroots.keys())
457
+ else:
458
+ k_max = S.Zero
459
+
460
+ ind, mp = S.Zero, -oo
461
+ for i in range(k_max + m + 1):
462
+ r = f.diff(x, i).limit(x, 0) / factorial(i)
463
+ if r.is_finite is False:
464
+ old_f = f
465
+ f, P, Q, m = _transformation_a(f, x, P, Q, k, m, i)
466
+ f, P, Q, m = _transformation_e(f, x, P, Q, k, m)
467
+ sol, ind, mp = _rsolve_hypergeometric(f, x, P, Q, k, m)
468
+ sol = _apply_integrate(sol, x, k)
469
+ sol = _apply_shift(sol, i)
470
+ ind = integrate(ind, x)
471
+ ind += (old_f - ind).limit(x, 0) # constant of integration
472
+ mp += 1
473
+ return sol, ind, mp
474
+ elif r:
475
+ ind += r*x**(i + shift)
476
+ pow_x = Rational((i + shift), scale)
477
+ if pow_x > mp:
478
+ mp = pow_x # maximum power of x
479
+ ind = ind.subs(x, x**(1/scale))
480
+
481
+ sol = _compute_formula(f, x, P, Q, k, m, k_max)
482
+ sol = _apply_shift(sol, shift)
483
+ sol = _apply_scale(sol, scale)
484
+
485
+ return sol, ind, mp
486
+
487
+
488
+ def rsolve_hypergeometric(f, x, P, Q, k, m):
489
+ """
490
+ Solves RE of hypergeometric type.
491
+
492
+ Explanation
493
+ ===========
494
+
495
+ Attempts to solve RE of the form
496
+
497
+ Q(k)*a(k + m) - P(k)*a(k)
498
+
499
+ Transformations that preserve Hypergeometric type:
500
+
501
+ a. x**n*f(x): b(k + m) = R(k - n)*b(k)
502
+ b. f(A*x): b(k + m) = A**m*R(k)*b(k)
503
+ c. f(x**n): b(k + n*m) = R(k/n)*b(k)
504
+ d. f(x**(1/m)): b(k + 1) = R(k*m)*b(k)
505
+ e. f'(x): b(k + m) = ((k + m + 1)/(k + 1))*R(k + 1)*b(k)
506
+
507
+ Some of these transformations have been used to solve the RE.
508
+
509
+ Returns
510
+ =======
511
+
512
+ formula : Expr
513
+ ind : Expr
514
+ Independent terms.
515
+ order : int
516
+
517
+ Examples
518
+ ========
519
+
520
+ >>> from sympy import exp, ln, S
521
+ >>> from sympy.series.formal import rsolve_hypergeometric as rh
522
+ >>> from sympy.abc import x, k
523
+
524
+ >>> rh(exp(x), x, -S.One, (k + 1), k, 1)
525
+ (Piecewise((1/factorial(k), Eq(Mod(k, 1), 0)), (0, True)), 1, 1)
526
+
527
+ >>> rh(ln(1 + x), x, k**2, k*(k + 1), k, 1)
528
+ (Piecewise(((-1)**(k - 1)*factorial(k - 1)/RisingFactorial(2, k - 1),
529
+ Eq(Mod(k, 1), 0)), (0, True)), x, 2)
530
+
531
+ References
532
+ ==========
533
+
534
+ .. [1] Formal Power Series - Dominik Gruntz, Wolfram Koepf
535
+ .. [2] Power Series in Computer Algebra - Wolfram Koepf
536
+ """
537
+ result = _rsolve_hypergeometric(f, x, P, Q, k, m)
538
+
539
+ if result is None:
540
+ return None
541
+
542
+ sol_list, ind, mp = result
543
+
544
+ sol_dict = defaultdict(lambda: S.Zero)
545
+ for res, cond in sol_list:
546
+ j, mk = cond.as_coeff_Add()
547
+ c = mk.coeff(k)
548
+
549
+ if j.is_integer is False:
550
+ res *= x**frac(j)
551
+ j = floor(j)
552
+
553
+ res = res.subs(k, (k - j) / c)
554
+ cond = Eq(k % c, j % c)
555
+ sol_dict[cond] += res # Group together formula for same conditions
556
+
557
+ sol = []
558
+ for cond, res in sol_dict.items():
559
+ sol.append((res, cond))
560
+ sol.append((S.Zero, True))
561
+ sol = Piecewise(*sol)
562
+
563
+ if mp is -oo:
564
+ s = S.Zero
565
+ elif mp.is_integer is False:
566
+ s = ceiling(mp)
567
+ else:
568
+ s = mp + 1
569
+
570
+ # save all the terms of
571
+ # form 1/x**k in ind
572
+ if s < 0:
573
+ ind += sum(sequence(sol * x**k, (k, s, -1)))
574
+ s = S.Zero
575
+
576
+ return (sol, ind, s)
577
+
578
+
579
+ def _solve_hyper_RE(f, x, RE, g, k):
580
+ """See docstring of :func:`rsolve_hypergeometric` for details."""
581
+ terms = Add.make_args(RE)
582
+
583
+ if len(terms) == 2:
584
+ gs = list(RE.atoms(Function))
585
+ P, Q = map(RE.coeff, gs)
586
+ m = gs[1].args[0] - gs[0].args[0]
587
+ if m < 0:
588
+ P, Q = Q, P
589
+ m = abs(m)
590
+ return rsolve_hypergeometric(f, x, P, Q, k, m)
591
+
592
+
593
+ def _solve_explike_DE(f, x, DE, g, k):
594
+ """Solves DE with constant coefficients."""
595
+ from sympy.solvers import rsolve
596
+
597
+ for t in Add.make_args(DE):
598
+ coeff, d = t.as_independent(g)
599
+ if coeff.free_symbols:
600
+ return
601
+
602
+ RE = exp_re(DE, g, k)
603
+
604
+ init = {}
605
+ for i in range(len(Add.make_args(RE))):
606
+ if i:
607
+ f = f.diff(x)
608
+ init[g(k).subs(k, i)] = f.limit(x, 0)
609
+
610
+ sol = rsolve(RE, g(k), init)
611
+
612
+ if sol:
613
+ return (sol / factorial(k), S.Zero, S.Zero)
614
+
615
+
616
+ def _solve_simple(f, x, DE, g, k):
617
+ """Converts DE into RE and solves using :func:`rsolve`."""
618
+ from sympy.solvers import rsolve
619
+
620
+ RE = hyper_re(DE, g, k)
621
+
622
+ init = {}
623
+ for i in range(len(Add.make_args(RE))):
624
+ if i:
625
+ f = f.diff(x)
626
+ init[g(k).subs(k, i)] = f.limit(x, 0) / factorial(i)
627
+
628
+ sol = rsolve(RE, g(k), init)
629
+
630
+ if sol:
631
+ return (sol, S.Zero, S.Zero)
632
+
633
+
634
+ def _transform_explike_DE(DE, g, x, order, syms):
635
+ """Converts DE with free parameters into DE with constant coefficients."""
636
+ from sympy.solvers.solveset import linsolve
637
+
638
+ eq = []
639
+ highest_coeff = DE.coeff(Derivative(g(x), x, order))
640
+ for i in range(order):
641
+ coeff = DE.coeff(Derivative(g(x), x, i))
642
+ coeff = (coeff / highest_coeff).expand().collect(x)
643
+ for t in Add.make_args(coeff):
644
+ eq.append(t)
645
+ temp = []
646
+ for e in eq:
647
+ if e.has(x):
648
+ break
649
+ elif e.has(Symbol):
650
+ temp.append(e)
651
+ else:
652
+ eq = temp
653
+ if eq:
654
+ sol = dict(zip(syms, (i for s in linsolve(eq, list(syms)) for i in s)))
655
+ if sol:
656
+ DE = DE.subs(sol)
657
+ DE = DE.factor().as_coeff_mul(Derivative)[1][0]
658
+ DE = DE.collect(Derivative(g(x)))
659
+ return DE
660
+
661
+
662
+ def _transform_DE_RE(DE, g, k, order, syms):
663
+ """Converts DE with free parameters into RE of hypergeometric type."""
664
+ from sympy.solvers.solveset import linsolve
665
+
666
+ RE = hyper_re(DE, g, k)
667
+
668
+ eq = []
669
+ for i in range(1, order):
670
+ coeff = RE.coeff(g(k + i))
671
+ eq.append(coeff)
672
+ sol = dict(zip(syms, (i for s in linsolve(eq, list(syms)) for i in s)))
673
+ if sol:
674
+ m = Wild('m')
675
+ RE = RE.subs(sol)
676
+ RE = RE.factor().as_numer_denom()[0].collect(g(k + m))
677
+ RE = RE.as_coeff_mul(g)[1][0]
678
+ for i in range(order): # smallest order should be g(k)
679
+ if RE.coeff(g(k + i)) and i:
680
+ RE = RE.subs(k, k - i)
681
+ break
682
+ return RE
683
+
684
+
685
+ def solve_de(f, x, DE, order, g, k):
686
+ """
687
+ Solves the DE.
688
+
689
+ Explanation
690
+ ===========
691
+
692
+ Tries to solve DE by either converting into a RE containing two terms or
693
+ converting into a DE having constant coefficients.
694
+
695
+ Returns
696
+ =======
697
+
698
+ formula : Expr
699
+ ind : Expr
700
+ Independent terms.
701
+ order : int
702
+
703
+ Examples
704
+ ========
705
+
706
+ >>> from sympy import Derivative as D, Function
707
+ >>> from sympy import exp, ln
708
+ >>> from sympy.series.formal import solve_de
709
+ >>> from sympy.abc import x, k
710
+ >>> f = Function('f')
711
+
712
+ >>> solve_de(exp(x), x, D(f(x), x) - f(x), 1, f, k)
713
+ (Piecewise((1/factorial(k), Eq(Mod(k, 1), 0)), (0, True)), 1, 1)
714
+
715
+ >>> solve_de(ln(1 + x), x, (x + 1)*D(f(x), x, 2) + D(f(x)), 2, f, k)
716
+ (Piecewise(((-1)**(k - 1)*factorial(k - 1)/RisingFactorial(2, k - 1),
717
+ Eq(Mod(k, 1), 0)), (0, True)), x, 2)
718
+ """
719
+ sol = None
720
+ syms = DE.free_symbols.difference({g, x})
721
+
722
+ if syms:
723
+ RE = _transform_DE_RE(DE, g, k, order, syms)
724
+ else:
725
+ RE = hyper_re(DE, g, k)
726
+ if not RE.free_symbols.difference({k}):
727
+ sol = _solve_hyper_RE(f, x, RE, g, k)
728
+
729
+ if sol:
730
+ return sol
731
+
732
+ if syms:
733
+ DE = _transform_explike_DE(DE, g, x, order, syms)
734
+ if not DE.free_symbols.difference({x}):
735
+ sol = _solve_explike_DE(f, x, DE, g, k)
736
+
737
+ if sol:
738
+ return sol
739
+
740
+
741
+ def hyper_algorithm(f, x, k, order=4):
742
+ """
743
+ Hypergeometric algorithm for computing Formal Power Series.
744
+
745
+ Explanation
746
+ ===========
747
+
748
+ Steps:
749
+ * Generates DE
750
+ * Convert the DE into RE
751
+ * Solves the RE
752
+
753
+ Examples
754
+ ========
755
+
756
+ >>> from sympy import exp, ln
757
+ >>> from sympy.series.formal import hyper_algorithm
758
+
759
+ >>> from sympy.abc import x, k
760
+
761
+ >>> hyper_algorithm(exp(x), x, k)
762
+ (Piecewise((1/factorial(k), Eq(Mod(k, 1), 0)), (0, True)), 1, 1)
763
+
764
+ >>> hyper_algorithm(ln(1 + x), x, k)
765
+ (Piecewise(((-1)**(k - 1)*factorial(k - 1)/RisingFactorial(2, k - 1),
766
+ Eq(Mod(k, 1), 0)), (0, True)), x, 2)
767
+
768
+ See Also
769
+ ========
770
+
771
+ sympy.series.formal.simpleDE
772
+ sympy.series.formal.solve_de
773
+ """
774
+ g = Function('g')
775
+
776
+ des = [] # list of DE's
777
+ sol = None
778
+ for DE, i in simpleDE(f, x, g, order):
779
+ if DE is not None:
780
+ sol = solve_de(f, x, DE, i, g, k)
781
+ if sol:
782
+ return sol
783
+ if not DE.free_symbols.difference({x}):
784
+ des.append(DE)
785
+
786
+ # If nothing works
787
+ # Try plain rsolve
788
+ for DE in des:
789
+ sol = _solve_simple(f, x, DE, g, k)
790
+ if sol:
791
+ return sol
792
+
793
+
794
+ def _compute_fps(f, x, x0, dir, hyper, order, rational, full):
795
+ """Recursive wrapper to compute fps.
796
+
797
+ See :func:`compute_fps` for details.
798
+ """
799
+ if x0 in [S.Infinity, S.NegativeInfinity]:
800
+ dir = S.One if x0 is S.Infinity else -S.One
801
+ temp = f.subs(x, 1/x)
802
+ result = _compute_fps(temp, x, 0, dir, hyper, order, rational, full)
803
+ if result is None:
804
+ return None
805
+ return (result[0], result[1].subs(x, 1/x), result[2].subs(x, 1/x))
806
+ elif x0 or dir == -S.One:
807
+ if dir == -S.One:
808
+ rep = -x + x0
809
+ rep2 = -x
810
+ rep2b = x0
811
+ else:
812
+ rep = x + x0
813
+ rep2 = x
814
+ rep2b = -x0
815
+ temp = f.subs(x, rep)
816
+ result = _compute_fps(temp, x, 0, S.One, hyper, order, rational, full)
817
+ if result is None:
818
+ return None
819
+ return (result[0], result[1].subs(x, rep2 + rep2b),
820
+ result[2].subs(x, rep2 + rep2b))
821
+
822
+ if f.is_polynomial(x):
823
+ k = Dummy('k')
824
+ ak = sequence(Coeff(f, x, k), (k, 1, oo))
825
+ xk = sequence(x**k, (k, 0, oo))
826
+ ind = f.coeff(x, 0)
827
+ return ak, xk, ind
828
+
829
+ # Break instances of Add
830
+ # this allows application of different
831
+ # algorithms on different terms increasing the
832
+ # range of admissible functions.
833
+ if isinstance(f, Add):
834
+ result = False
835
+ ak = sequence(S.Zero, (0, oo))
836
+ ind, xk = S.Zero, None
837
+ for t in Add.make_args(f):
838
+ res = _compute_fps(t, x, 0, S.One, hyper, order, rational, full)
839
+ if res:
840
+ if not result:
841
+ result = True
842
+ xk = res[1]
843
+ if res[0].start > ak.start:
844
+ seq = ak
845
+ s, f = ak.start, res[0].start
846
+ else:
847
+ seq = res[0]
848
+ s, f = res[0].start, ak.start
849
+ save = Add(*[z[0]*z[1] for z in zip(seq[0:(f - s)], xk[s:f])])
850
+ ak += res[0]
851
+ ind += res[2] + save
852
+ else:
853
+ ind += t
854
+ if result:
855
+ return ak, xk, ind
856
+ return None
857
+
858
+ # The symbolic term - symb, if present, is being separated from the function
859
+ # Otherwise symb is being set to S.One
860
+ syms = f.free_symbols.difference({x})
861
+ (f, symb) = expand(f).as_independent(*syms)
862
+
863
+ result = None
864
+
865
+ # from here on it's x0=0 and dir=1 handling
866
+ k = Dummy('k')
867
+ if rational:
868
+ result = rational_algorithm(f, x, k, order, full)
869
+
870
+ if result is None and hyper:
871
+ result = hyper_algorithm(f, x, k, order)
872
+
873
+ if result is None:
874
+ return None
875
+
876
+ from sympy.simplify.powsimp import powsimp
877
+ if symb.is_zero:
878
+ symb = S.One
879
+ else:
880
+ symb = powsimp(symb)
881
+ ak = sequence(result[0], (k, result[2], oo))
882
+ xk_formula = powsimp(x**k * symb)
883
+ xk = sequence(xk_formula, (k, 0, oo))
884
+ ind = powsimp(result[1] * symb)
885
+
886
+ return ak, xk, ind
887
+
888
+
889
+ def compute_fps(f, x, x0=0, dir=1, hyper=True, order=4, rational=True,
890
+ full=False):
891
+ """
892
+ Computes the formula for Formal Power Series of a function.
893
+
894
+ Explanation
895
+ ===========
896
+
897
+ Tries to compute the formula by applying the following techniques
898
+ (in order):
899
+
900
+ * rational_algorithm
901
+ * Hypergeometric algorithm
902
+
903
+ Parameters
904
+ ==========
905
+
906
+ x : Symbol
907
+ x0 : number, optional
908
+ Point to perform series expansion about. Default is 0.
909
+ dir : {1, -1, '+', '-'}, optional
910
+ If dir is 1 or '+' the series is calculated from the right and
911
+ for -1 or '-' the series is calculated from the left. For smooth
912
+ functions this flag will not alter the results. Default is 1.
913
+ hyper : {True, False}, optional
914
+ Set hyper to False to skip the hypergeometric algorithm.
915
+ By default it is set to False.
916
+ order : int, optional
917
+ Order of the derivative of ``f``, Default is 4.
918
+ rational : {True, False}, optional
919
+ Set rational to False to skip rational algorithm. By default it is set
920
+ to True.
921
+ full : {True, False}, optional
922
+ Set full to True to increase the range of rational algorithm.
923
+ See :func:`rational_algorithm` for details. By default it is set to
924
+ False.
925
+
926
+ Returns
927
+ =======
928
+
929
+ ak : sequence
930
+ Sequence of coefficients.
931
+ xk : sequence
932
+ Sequence of powers of x.
933
+ ind : Expr
934
+ Independent terms.
935
+ mul : Pow
936
+ Common terms.
937
+
938
+ See Also
939
+ ========
940
+
941
+ sympy.series.formal.rational_algorithm
942
+ sympy.series.formal.hyper_algorithm
943
+ """
944
+ f = sympify(f)
945
+ x = sympify(x)
946
+
947
+ if not f.has(x):
948
+ return None
949
+
950
+ x0 = sympify(x0)
951
+
952
+ if dir == '+':
953
+ dir = S.One
954
+ elif dir == '-':
955
+ dir = -S.One
956
+ elif dir not in [S.One, -S.One]:
957
+ raise ValueError("Dir must be '+' or '-'")
958
+ else:
959
+ dir = sympify(dir)
960
+
961
+ return _compute_fps(f, x, x0, dir, hyper, order, rational, full)
962
+
963
+
964
+ class Coeff(Function):
965
+ """
966
+ Coeff(p, x, n) represents the nth coefficient of the polynomial p in x
967
+ """
968
+ @classmethod
969
+ def eval(cls, p, x, n):
970
+ if p.is_polynomial(x) and n.is_integer:
971
+ return p.coeff(x, n)
972
+
973
+
974
+ class FormalPowerSeries(SeriesBase):
975
+ """
976
+ Represents Formal Power Series of a function.
977
+
978
+ Explanation
979
+ ===========
980
+
981
+ No computation is performed. This class should only to be used to represent
982
+ a series. No checks are performed.
983
+
984
+ For computing a series use :func:`fps`.
985
+
986
+ See Also
987
+ ========
988
+
989
+ sympy.series.formal.fps
990
+ """
991
+ def __new__(cls, *args):
992
+ args = map(sympify, args)
993
+ return Expr.__new__(cls, *args)
994
+
995
+ def __init__(self, *args):
996
+ ak = args[4][0]
997
+ k = ak.variables[0]
998
+ self.ak_seq = sequence(ak.formula, (k, 1, oo))
999
+ self.fact_seq = sequence(factorial(k), (k, 1, oo))
1000
+ self.bell_coeff_seq = self.ak_seq * self.fact_seq
1001
+ self.sign_seq = sequence((-1, 1), (k, 1, oo))
1002
+
1003
+ @property
1004
+ def function(self):
1005
+ return self.args[0]
1006
+
1007
+ @property
1008
+ def x(self):
1009
+ return self.args[1]
1010
+
1011
+ @property
1012
+ def x0(self):
1013
+ return self.args[2]
1014
+
1015
+ @property
1016
+ def dir(self):
1017
+ return self.args[3]
1018
+
1019
+ @property
1020
+ def ak(self):
1021
+ return self.args[4][0]
1022
+
1023
+ @property
1024
+ def xk(self):
1025
+ return self.args[4][1]
1026
+
1027
+ @property
1028
+ def ind(self):
1029
+ return self.args[4][2]
1030
+
1031
+ @property
1032
+ def interval(self):
1033
+ return Interval(0, oo)
1034
+
1035
+ @property
1036
+ def start(self):
1037
+ return self.interval.inf
1038
+
1039
+ @property
1040
+ def stop(self):
1041
+ return self.interval.sup
1042
+
1043
+ @property
1044
+ def length(self):
1045
+ return oo
1046
+
1047
+ @property
1048
+ def infinite(self):
1049
+ """Returns an infinite representation of the series"""
1050
+ from sympy.concrete import Sum
1051
+ ak, xk = self.ak, self.xk
1052
+ k = ak.variables[0]
1053
+ inf_sum = Sum(ak.formula * xk.formula, (k, ak.start, ak.stop))
1054
+
1055
+ return self.ind + inf_sum
1056
+
1057
+ def _get_pow_x(self, term):
1058
+ """Returns the power of x in a term."""
1059
+ xterm, pow_x = term.as_independent(self.x)[1].as_base_exp()
1060
+ if not xterm.has(self.x):
1061
+ return S.Zero
1062
+ return pow_x
1063
+
1064
+ def polynomial(self, n=6):
1065
+ """
1066
+ Truncated series as polynomial.
1067
+
1068
+ Explanation
1069
+ ===========
1070
+
1071
+ Returns series expansion of ``f`` upto order ``O(x**n)``
1072
+ as a polynomial(without ``O`` term).
1073
+ """
1074
+ terms = []
1075
+ sym = self.free_symbols
1076
+ for i, t in enumerate(self):
1077
+ xp = self._get_pow_x(t)
1078
+ if xp.has(*sym):
1079
+ xp = xp.as_coeff_add(*sym)[0]
1080
+ if xp >= n:
1081
+ break
1082
+ elif xp.is_integer is True and i == n + 1:
1083
+ break
1084
+ elif t is not S.Zero:
1085
+ terms.append(t)
1086
+
1087
+ return Add(*terms)
1088
+
1089
+ def truncate(self, n=6):
1090
+ """
1091
+ Truncated series.
1092
+
1093
+ Explanation
1094
+ ===========
1095
+
1096
+ Returns truncated series expansion of f upto
1097
+ order ``O(x**n)``.
1098
+
1099
+ If n is ``None``, returns an infinite iterator.
1100
+ """
1101
+ if n is None:
1102
+ return iter(self)
1103
+
1104
+ x, x0 = self.x, self.x0
1105
+ pt_xk = self.xk.coeff(n)
1106
+ if x0 is S.NegativeInfinity:
1107
+ x0 = S.Infinity
1108
+
1109
+ return self.polynomial(n) + Order(pt_xk, (x, x0))
1110
+
1111
+ def zero_coeff(self):
1112
+ return self._eval_term(0)
1113
+
1114
+ def _eval_term(self, pt):
1115
+ try:
1116
+ pt_xk = self.xk.coeff(pt)
1117
+ pt_ak = self.ak.coeff(pt).simplify() # Simplify the coefficients
1118
+ except IndexError:
1119
+ term = S.Zero
1120
+ else:
1121
+ term = (pt_ak * pt_xk)
1122
+
1123
+ if self.ind:
1124
+ ind = S.Zero
1125
+ sym = self.free_symbols
1126
+ for t in Add.make_args(self.ind):
1127
+ pow_x = self._get_pow_x(t)
1128
+ if pow_x.has(*sym):
1129
+ pow_x = pow_x.as_coeff_add(*sym)[0]
1130
+ if pt == 0 and pow_x < 1:
1131
+ ind += t
1132
+ elif pow_x >= pt and pow_x < pt + 1:
1133
+ ind += t
1134
+ term += ind
1135
+
1136
+ return term.collect(self.x)
1137
+
1138
+ def _eval_subs(self, old, new):
1139
+ x = self.x
1140
+ if old.has(x):
1141
+ return self
1142
+
1143
+ def _eval_as_leading_term(self, x, logx=None, cdir=0):
1144
+ for t in self:
1145
+ if t is not S.Zero:
1146
+ return t
1147
+
1148
+ def _eval_derivative(self, x):
1149
+ f = self.function.diff(x)
1150
+ ind = self.ind.diff(x)
1151
+
1152
+ pow_xk = self._get_pow_x(self.xk.formula)
1153
+ ak = self.ak
1154
+ k = ak.variables[0]
1155
+ if ak.formula.has(x):
1156
+ form = []
1157
+ for e, c in ak.formula.args:
1158
+ temp = S.Zero
1159
+ for t in Add.make_args(e):
1160
+ pow_x = self._get_pow_x(t)
1161
+ temp += t * (pow_xk + pow_x)
1162
+ form.append((temp, c))
1163
+ form = Piecewise(*form)
1164
+ ak = sequence(form.subs(k, k + 1), (k, ak.start - 1, ak.stop))
1165
+ else:
1166
+ ak = sequence((ak.formula * pow_xk).subs(k, k + 1),
1167
+ (k, ak.start - 1, ak.stop))
1168
+
1169
+ return self.func(f, self.x, self.x0, self.dir, (ak, self.xk, ind))
1170
+
1171
+ def integrate(self, x=None, **kwargs):
1172
+ """
1173
+ Integrate Formal Power Series.
1174
+
1175
+ Examples
1176
+ ========
1177
+
1178
+ >>> from sympy import fps, sin, integrate
1179
+ >>> from sympy.abc import x
1180
+ >>> f = fps(sin(x))
1181
+ >>> f.integrate(x).truncate()
1182
+ -1 + x**2/2 - x**4/24 + O(x**6)
1183
+ >>> integrate(f, (x, 0, 1))
1184
+ 1 - cos(1)
1185
+ """
1186
+ from sympy.integrals import integrate
1187
+
1188
+ if x is None:
1189
+ x = self.x
1190
+ elif iterable(x):
1191
+ return integrate(self.function, x)
1192
+
1193
+ f = integrate(self.function, x)
1194
+ ind = integrate(self.ind, x)
1195
+ ind += (f - ind).limit(x, 0) # constant of integration
1196
+
1197
+ pow_xk = self._get_pow_x(self.xk.formula)
1198
+ ak = self.ak
1199
+ k = ak.variables[0]
1200
+ if ak.formula.has(x):
1201
+ form = []
1202
+ for e, c in ak.formula.args:
1203
+ temp = S.Zero
1204
+ for t in Add.make_args(e):
1205
+ pow_x = self._get_pow_x(t)
1206
+ temp += t / (pow_xk + pow_x + 1)
1207
+ form.append((temp, c))
1208
+ form = Piecewise(*form)
1209
+ ak = sequence(form.subs(k, k - 1), (k, ak.start + 1, ak.stop))
1210
+ else:
1211
+ ak = sequence((ak.formula / (pow_xk + 1)).subs(k, k - 1),
1212
+ (k, ak.start + 1, ak.stop))
1213
+
1214
+ return self.func(f, self.x, self.x0, self.dir, (ak, self.xk, ind))
1215
+
1216
+ def product(self, other, x=None, n=6):
1217
+ """
1218
+ Multiplies two Formal Power Series, using discrete convolution and
1219
+ return the truncated terms upto specified order.
1220
+
1221
+ Parameters
1222
+ ==========
1223
+
1224
+ n : Number, optional
1225
+ Specifies the order of the term up to which the polynomial should
1226
+ be truncated.
1227
+
1228
+ Examples
1229
+ ========
1230
+
1231
+ >>> from sympy import fps, sin, exp
1232
+ >>> from sympy.abc import x
1233
+ >>> f1 = fps(sin(x))
1234
+ >>> f2 = fps(exp(x))
1235
+
1236
+ >>> f1.product(f2, x).truncate(4)
1237
+ x + x**2 + x**3/3 + O(x**4)
1238
+
1239
+ See Also
1240
+ ========
1241
+
1242
+ sympy.discrete.convolutions
1243
+ sympy.series.formal.FormalPowerSeriesProduct
1244
+
1245
+ """
1246
+
1247
+ if n is None:
1248
+ return iter(self)
1249
+
1250
+ other = sympify(other)
1251
+
1252
+ if not isinstance(other, FormalPowerSeries):
1253
+ raise ValueError("Both series should be an instance of FormalPowerSeries"
1254
+ " class.")
1255
+
1256
+ if self.dir != other.dir:
1257
+ raise ValueError("Both series should be calculated from the"
1258
+ " same direction.")
1259
+ elif self.x0 != other.x0:
1260
+ raise ValueError("Both series should be calculated about the"
1261
+ " same point.")
1262
+
1263
+ elif self.x != other.x:
1264
+ raise ValueError("Both series should have the same symbol.")
1265
+
1266
+ return FormalPowerSeriesProduct(self, other)
1267
+
1268
+ def coeff_bell(self, n):
1269
+ r"""
1270
+ self.coeff_bell(n) returns a sequence of Bell polynomials of the second kind.
1271
+ Note that ``n`` should be a integer.
1272
+
1273
+ The second kind of Bell polynomials (are sometimes called "partial" Bell
1274
+ polynomials or incomplete Bell polynomials) are defined as
1275
+
1276
+ .. math::
1277
+ B_{n,k}(x_1, x_2,\dotsc x_{n-k+1}) =
1278
+ \sum_{j_1+j_2+j_2+\dotsb=k \atop j_1+2j_2+3j_2+\dotsb=n}
1279
+ \frac{n!}{j_1!j_2!\dotsb j_{n-k+1}!}
1280
+ \left(\frac{x_1}{1!} \right)^{j_1}
1281
+ \left(\frac{x_2}{2!} \right)^{j_2} \dotsb
1282
+ \left(\frac{x_{n-k+1}}{(n-k+1)!} \right) ^{j_{n-k+1}}.
1283
+
1284
+ * ``bell(n, k, (x1, x2, ...))`` gives Bell polynomials of the second kind,
1285
+ `B_{n,k}(x_1, x_2, \dotsc, x_{n-k+1})`.
1286
+
1287
+ See Also
1288
+ ========
1289
+
1290
+ sympy.functions.combinatorial.numbers.bell
1291
+
1292
+ """
1293
+
1294
+ inner_coeffs = [bell(n, j, tuple(self.bell_coeff_seq[:n-j+1])) for j in range(1, n+1)]
1295
+
1296
+ k = Dummy('k')
1297
+ return sequence(tuple(inner_coeffs), (k, 1, oo))
1298
+
1299
+ def compose(self, other, x=None, n=6):
1300
+ r"""
1301
+ Returns the truncated terms of the formal power series of the composed function,
1302
+ up to specified ``n``.
1303
+
1304
+ Explanation
1305
+ ===========
1306
+
1307
+ If ``f`` and ``g`` are two formal power series of two different functions,
1308
+ then the coefficient sequence ``ak`` of the composed formal power series `fp`
1309
+ will be as follows.
1310
+
1311
+ .. math::
1312
+ \sum\limits_{k=0}^{n} b_k B_{n,k}(x_1, x_2, \dotsc, x_{n-k+1})
1313
+
1314
+ Parameters
1315
+ ==========
1316
+
1317
+ n : Number, optional
1318
+ Specifies the order of the term up to which the polynomial should
1319
+ be truncated.
1320
+
1321
+ Examples
1322
+ ========
1323
+
1324
+ >>> from sympy import fps, sin, exp
1325
+ >>> from sympy.abc import x
1326
+ >>> f1 = fps(exp(x))
1327
+ >>> f2 = fps(sin(x))
1328
+
1329
+ >>> f1.compose(f2, x).truncate()
1330
+ 1 + x + x**2/2 - x**4/8 - x**5/15 + O(x**6)
1331
+
1332
+ >>> f1.compose(f2, x).truncate(8)
1333
+ 1 + x + x**2/2 - x**4/8 - x**5/15 - x**6/240 + x**7/90 + O(x**8)
1334
+
1335
+ See Also
1336
+ ========
1337
+
1338
+ sympy.functions.combinatorial.numbers.bell
1339
+ sympy.series.formal.FormalPowerSeriesCompose
1340
+
1341
+ References
1342
+ ==========
1343
+
1344
+ .. [1] Comtet, Louis: Advanced combinatorics; the art of finite and infinite expansions. Reidel, 1974.
1345
+
1346
+ """
1347
+
1348
+ if n is None:
1349
+ return iter(self)
1350
+
1351
+ other = sympify(other)
1352
+
1353
+ if not isinstance(other, FormalPowerSeries):
1354
+ raise ValueError("Both series should be an instance of FormalPowerSeries"
1355
+ " class.")
1356
+
1357
+ if self.dir != other.dir:
1358
+ raise ValueError("Both series should be calculated from the"
1359
+ " same direction.")
1360
+ elif self.x0 != other.x0:
1361
+ raise ValueError("Both series should be calculated about the"
1362
+ " same point.")
1363
+
1364
+ elif self.x != other.x:
1365
+ raise ValueError("Both series should have the same symbol.")
1366
+
1367
+ if other._eval_term(0).as_coeff_mul(other.x)[0] is not S.Zero:
1368
+ raise ValueError("The formal power series of the inner function should not have any "
1369
+ "constant coefficient term.")
1370
+
1371
+ return FormalPowerSeriesCompose(self, other)
1372
+
1373
+ def inverse(self, x=None, n=6):
1374
+ r"""
1375
+ Returns the truncated terms of the inverse of the formal power series,
1376
+ up to specified ``n``.
1377
+
1378
+ Explanation
1379
+ ===========
1380
+
1381
+ If ``f`` and ``g`` are two formal power series of two different functions,
1382
+ then the coefficient sequence ``ak`` of the composed formal power series ``fp``
1383
+ will be as follows.
1384
+
1385
+ .. math::
1386
+ \sum\limits_{k=0}^{n} (-1)^{k} x_0^{-k-1} B_{n,k}(x_1, x_2, \dotsc, x_{n-k+1})
1387
+
1388
+ Parameters
1389
+ ==========
1390
+
1391
+ n : Number, optional
1392
+ Specifies the order of the term up to which the polynomial should
1393
+ be truncated.
1394
+
1395
+ Examples
1396
+ ========
1397
+
1398
+ >>> from sympy import fps, exp, cos
1399
+ >>> from sympy.abc import x
1400
+ >>> f1 = fps(exp(x))
1401
+ >>> f2 = fps(cos(x))
1402
+
1403
+ >>> f1.inverse(x).truncate()
1404
+ 1 - x + x**2/2 - x**3/6 + x**4/24 - x**5/120 + O(x**6)
1405
+
1406
+ >>> f2.inverse(x).truncate(8)
1407
+ 1 + x**2/2 + 5*x**4/24 + 61*x**6/720 + O(x**8)
1408
+
1409
+ See Also
1410
+ ========
1411
+
1412
+ sympy.functions.combinatorial.numbers.bell
1413
+ sympy.series.formal.FormalPowerSeriesInverse
1414
+
1415
+ References
1416
+ ==========
1417
+
1418
+ .. [1] Comtet, Louis: Advanced combinatorics; the art of finite and infinite expansions. Reidel, 1974.
1419
+
1420
+ """
1421
+
1422
+ if n is None:
1423
+ return iter(self)
1424
+
1425
+ if self._eval_term(0).is_zero:
1426
+ raise ValueError("Constant coefficient should exist for an inverse of a formal"
1427
+ " power series to exist.")
1428
+
1429
+ return FormalPowerSeriesInverse(self)
1430
+
1431
+ def __add__(self, other):
1432
+ other = sympify(other)
1433
+
1434
+ if isinstance(other, FormalPowerSeries):
1435
+ if self.dir != other.dir:
1436
+ raise ValueError("Both series should be calculated from the"
1437
+ " same direction.")
1438
+ elif self.x0 != other.x0:
1439
+ raise ValueError("Both series should be calculated about the"
1440
+ " same point.")
1441
+
1442
+ x, y = self.x, other.x
1443
+ f = self.function + other.function.subs(y, x)
1444
+
1445
+ if self.x not in f.free_symbols:
1446
+ return f
1447
+
1448
+ ak = self.ak + other.ak
1449
+ if self.ak.start > other.ak.start:
1450
+ seq = other.ak
1451
+ s, e = other.ak.start, self.ak.start
1452
+ else:
1453
+ seq = self.ak
1454
+ s, e = self.ak.start, other.ak.start
1455
+ save = Add(*[z[0]*z[1] for z in zip(seq[0:(e - s)], self.xk[s:e])])
1456
+ ind = self.ind + other.ind + save
1457
+
1458
+ return self.func(f, x, self.x0, self.dir, (ak, self.xk, ind))
1459
+
1460
+ elif not other.has(self.x):
1461
+ f = self.function + other
1462
+ ind = self.ind + other
1463
+
1464
+ return self.func(f, self.x, self.x0, self.dir,
1465
+ (self.ak, self.xk, ind))
1466
+
1467
+ return Add(self, other)
1468
+
1469
+ def __radd__(self, other):
1470
+ return self.__add__(other)
1471
+
1472
+ def __neg__(self):
1473
+ return self.func(-self.function, self.x, self.x0, self.dir,
1474
+ (-self.ak, self.xk, -self.ind))
1475
+
1476
+ def __sub__(self, other):
1477
+ return self.__add__(-other)
1478
+
1479
+ def __rsub__(self, other):
1480
+ return (-self).__add__(other)
1481
+
1482
+ def __mul__(self, other):
1483
+ other = sympify(other)
1484
+
1485
+ if other.has(self.x):
1486
+ return Mul(self, other)
1487
+
1488
+ f = self.function * other
1489
+ ak = self.ak.coeff_mul(other)
1490
+ ind = self.ind * other
1491
+
1492
+ return self.func(f, self.x, self.x0, self.dir, (ak, self.xk, ind))
1493
+
1494
+ def __rmul__(self, other):
1495
+ return self.__mul__(other)
1496
+
1497
+
1498
+ class FiniteFormalPowerSeries(FormalPowerSeries):
1499
+ """Base Class for Product, Compose and Inverse classes"""
1500
+
1501
+ def __init__(self, *args):
1502
+ pass
1503
+
1504
+ @property
1505
+ def ffps(self):
1506
+ return self.args[0]
1507
+
1508
+ @property
1509
+ def gfps(self):
1510
+ return self.args[1]
1511
+
1512
+ @property
1513
+ def f(self):
1514
+ return self.ffps.function
1515
+
1516
+ @property
1517
+ def g(self):
1518
+ return self.gfps.function
1519
+
1520
+ @property
1521
+ def infinite(self):
1522
+ raise NotImplementedError("No infinite version for an object of"
1523
+ " FiniteFormalPowerSeries class.")
1524
+
1525
+ def _eval_terms(self, n):
1526
+ raise NotImplementedError("(%s)._eval_terms()" % self)
1527
+
1528
+ def _eval_term(self, pt):
1529
+ raise NotImplementedError("By the current logic, one can get terms"
1530
+ "upto a certain order, instead of getting term by term.")
1531
+
1532
+ def polynomial(self, n):
1533
+ return self._eval_terms(n)
1534
+
1535
+ def truncate(self, n=6):
1536
+ ffps = self.ffps
1537
+ pt_xk = ffps.xk.coeff(n)
1538
+ x, x0 = ffps.x, ffps.x0
1539
+
1540
+ return self.polynomial(n) + Order(pt_xk, (x, x0))
1541
+
1542
+ def _eval_derivative(self, x):
1543
+ raise NotImplementedError
1544
+
1545
+ def integrate(self, x):
1546
+ raise NotImplementedError
1547
+
1548
+
1549
+ class FormalPowerSeriesProduct(FiniteFormalPowerSeries):
1550
+ """Represents the product of two formal power series of two functions.
1551
+
1552
+ Explanation
1553
+ ===========
1554
+
1555
+ No computation is performed. Terms are calculated using a term by term logic,
1556
+ instead of a point by point logic.
1557
+
1558
+ There are two differences between a :obj:`FormalPowerSeries` object and a
1559
+ :obj:`FormalPowerSeriesProduct` object. The first argument contains the two
1560
+ functions involved in the product. Also, the coefficient sequence contains
1561
+ both the coefficient sequence of the formal power series of the involved functions.
1562
+
1563
+ See Also
1564
+ ========
1565
+
1566
+ sympy.series.formal.FormalPowerSeries
1567
+ sympy.series.formal.FiniteFormalPowerSeries
1568
+
1569
+ """
1570
+
1571
+ def __init__(self, *args):
1572
+ ffps, gfps = self.ffps, self.gfps
1573
+
1574
+ k = ffps.ak.variables[0]
1575
+ self.coeff1 = sequence(ffps.ak.formula, (k, 0, oo))
1576
+
1577
+ k = gfps.ak.variables[0]
1578
+ self.coeff2 = sequence(gfps.ak.formula, (k, 0, oo))
1579
+
1580
+ @property
1581
+ def function(self):
1582
+ """Function of the product of two formal power series."""
1583
+ return self.f * self.g
1584
+
1585
+ def _eval_terms(self, n):
1586
+ """
1587
+ Returns the first ``n`` terms of the product formal power series.
1588
+ Term by term logic is implemented here.
1589
+
1590
+ Examples
1591
+ ========
1592
+
1593
+ >>> from sympy import fps, sin, exp
1594
+ >>> from sympy.abc import x
1595
+ >>> f1 = fps(sin(x))
1596
+ >>> f2 = fps(exp(x))
1597
+ >>> fprod = f1.product(f2, x)
1598
+
1599
+ >>> fprod._eval_terms(4)
1600
+ x**3/3 + x**2 + x
1601
+
1602
+ See Also
1603
+ ========
1604
+
1605
+ sympy.series.formal.FormalPowerSeries.product
1606
+
1607
+ """
1608
+ coeff1, coeff2 = self.coeff1, self.coeff2
1609
+
1610
+ aks = convolution(coeff1[:n], coeff2[:n])
1611
+
1612
+ terms = []
1613
+ for i in range(0, n):
1614
+ terms.append(aks[i] * self.ffps.xk.coeff(i))
1615
+
1616
+ return Add(*terms)
1617
+
1618
+
1619
+ class FormalPowerSeriesCompose(FiniteFormalPowerSeries):
1620
+ """
1621
+ Represents the composed formal power series of two functions.
1622
+
1623
+ Explanation
1624
+ ===========
1625
+
1626
+ No computation is performed. Terms are calculated using a term by term logic,
1627
+ instead of a point by point logic.
1628
+
1629
+ There are two differences between a :obj:`FormalPowerSeries` object and a
1630
+ :obj:`FormalPowerSeriesCompose` object. The first argument contains the outer
1631
+ function and the inner function involved in the omposition. Also, the
1632
+ coefficient sequence contains the generic sequence which is to be multiplied
1633
+ by a custom ``bell_seq`` finite sequence. The finite terms will then be added up to
1634
+ get the final terms.
1635
+
1636
+ See Also
1637
+ ========
1638
+
1639
+ sympy.series.formal.FormalPowerSeries
1640
+ sympy.series.formal.FiniteFormalPowerSeries
1641
+
1642
+ """
1643
+
1644
+ @property
1645
+ def function(self):
1646
+ """Function for the composed formal power series."""
1647
+ f, g, x = self.f, self.g, self.ffps.x
1648
+ return f.subs(x, g)
1649
+
1650
+ def _eval_terms(self, n):
1651
+ """
1652
+ Returns the first `n` terms of the composed formal power series.
1653
+ Term by term logic is implemented here.
1654
+
1655
+ Explanation
1656
+ ===========
1657
+
1658
+ The coefficient sequence of the :obj:`FormalPowerSeriesCompose` object is the generic sequence.
1659
+ It is multiplied by ``bell_seq`` to get a sequence, whose terms are added up to get
1660
+ the final terms for the polynomial.
1661
+
1662
+ Examples
1663
+ ========
1664
+
1665
+ >>> from sympy import fps, sin, exp
1666
+ >>> from sympy.abc import x
1667
+ >>> f1 = fps(exp(x))
1668
+ >>> f2 = fps(sin(x))
1669
+ >>> fcomp = f1.compose(f2, x)
1670
+
1671
+ >>> fcomp._eval_terms(6)
1672
+ -x**5/15 - x**4/8 + x**2/2 + x + 1
1673
+
1674
+ >>> fcomp._eval_terms(8)
1675
+ x**7/90 - x**6/240 - x**5/15 - x**4/8 + x**2/2 + x + 1
1676
+
1677
+ See Also
1678
+ ========
1679
+
1680
+ sympy.series.formal.FormalPowerSeries.compose
1681
+ sympy.series.formal.FormalPowerSeries.coeff_bell
1682
+
1683
+ """
1684
+
1685
+ ffps, gfps = self.ffps, self.gfps
1686
+ terms = [ffps.zero_coeff()]
1687
+
1688
+ for i in range(1, n):
1689
+ bell_seq = gfps.coeff_bell(i)
1690
+ seq = (ffps.bell_coeff_seq * bell_seq)
1691
+ terms.append(Add(*(seq[:i])) / ffps.fact_seq[i-1] * ffps.xk.coeff(i))
1692
+
1693
+ return Add(*terms)
1694
+
1695
+
1696
+ class FormalPowerSeriesInverse(FiniteFormalPowerSeries):
1697
+ """
1698
+ Represents the Inverse of a formal power series.
1699
+
1700
+ Explanation
1701
+ ===========
1702
+
1703
+ No computation is performed. Terms are calculated using a term by term logic,
1704
+ instead of a point by point logic.
1705
+
1706
+ There is a single difference between a :obj:`FormalPowerSeries` object and a
1707
+ :obj:`FormalPowerSeriesInverse` object. The coefficient sequence contains the
1708
+ generic sequence which is to be multiplied by a custom ``bell_seq`` finite sequence.
1709
+ The finite terms will then be added up to get the final terms.
1710
+
1711
+ See Also
1712
+ ========
1713
+
1714
+ sympy.series.formal.FormalPowerSeries
1715
+ sympy.series.formal.FiniteFormalPowerSeries
1716
+
1717
+ """
1718
+ def __init__(self, *args):
1719
+ ffps = self.ffps
1720
+ k = ffps.xk.variables[0]
1721
+
1722
+ inv = ffps.zero_coeff()
1723
+ inv_seq = sequence(inv ** (-(k + 1)), (k, 1, oo))
1724
+ self.aux_seq = ffps.sign_seq * ffps.fact_seq * inv_seq
1725
+
1726
+ @property
1727
+ def function(self):
1728
+ """Function for the inverse of a formal power series."""
1729
+ f = self.f
1730
+ return 1 / f
1731
+
1732
+ @property
1733
+ def g(self):
1734
+ raise ValueError("Only one function is considered while performing"
1735
+ "inverse of a formal power series.")
1736
+
1737
+ @property
1738
+ def gfps(self):
1739
+ raise ValueError("Only one function is considered while performing"
1740
+ "inverse of a formal power series.")
1741
+
1742
+ def _eval_terms(self, n):
1743
+ """
1744
+ Returns the first ``n`` terms of the composed formal power series.
1745
+ Term by term logic is implemented here.
1746
+
1747
+ Explanation
1748
+ ===========
1749
+
1750
+ The coefficient sequence of the `FormalPowerSeriesInverse` object is the generic sequence.
1751
+ It is multiplied by ``bell_seq`` to get a sequence, whose terms are added up to get
1752
+ the final terms for the polynomial.
1753
+
1754
+ Examples
1755
+ ========
1756
+
1757
+ >>> from sympy import fps, exp, cos
1758
+ >>> from sympy.abc import x
1759
+ >>> f1 = fps(exp(x))
1760
+ >>> f2 = fps(cos(x))
1761
+ >>> finv1, finv2 = f1.inverse(), f2.inverse()
1762
+
1763
+ >>> finv1._eval_terms(6)
1764
+ -x**5/120 + x**4/24 - x**3/6 + x**2/2 - x + 1
1765
+
1766
+ >>> finv2._eval_terms(8)
1767
+ 61*x**6/720 + 5*x**4/24 + x**2/2 + 1
1768
+
1769
+ See Also
1770
+ ========
1771
+
1772
+ sympy.series.formal.FormalPowerSeries.inverse
1773
+ sympy.series.formal.FormalPowerSeries.coeff_bell
1774
+
1775
+ """
1776
+ ffps = self.ffps
1777
+ terms = [ffps.zero_coeff()]
1778
+
1779
+ for i in range(1, n):
1780
+ bell_seq = ffps.coeff_bell(i)
1781
+ seq = (self.aux_seq * bell_seq)
1782
+ terms.append(Add(*(seq[:i])) / ffps.fact_seq[i-1] * ffps.xk.coeff(i))
1783
+
1784
+ return Add(*terms)
1785
+
1786
+
1787
+ def fps(f, x=None, x0=0, dir=1, hyper=True, order=4, rational=True, full=False):
1788
+ """
1789
+ Generates Formal Power Series of ``f``.
1790
+
1791
+ Explanation
1792
+ ===========
1793
+
1794
+ Returns the formal series expansion of ``f`` around ``x = x0``
1795
+ with respect to ``x`` in the form of a ``FormalPowerSeries`` object.
1796
+
1797
+ Formal Power Series is represented using an explicit formula
1798
+ computed using different algorithms.
1799
+
1800
+ See :func:`compute_fps` for the more details regarding the computation
1801
+ of formula.
1802
+
1803
+ Parameters
1804
+ ==========
1805
+
1806
+ x : Symbol, optional
1807
+ If x is None and ``f`` is univariate, the univariate symbols will be
1808
+ supplied, otherwise an error will be raised.
1809
+ x0 : number, optional
1810
+ Point to perform series expansion about. Default is 0.
1811
+ dir : {1, -1, '+', '-'}, optional
1812
+ If dir is 1 or '+' the series is calculated from the right and
1813
+ for -1 or '-' the series is calculated from the left. For smooth
1814
+ functions this flag will not alter the results. Default is 1.
1815
+ hyper : {True, False}, optional
1816
+ Set hyper to False to skip the hypergeometric algorithm.
1817
+ By default it is set to False.
1818
+ order : int, optional
1819
+ Order of the derivative of ``f``, Default is 4.
1820
+ rational : {True, False}, optional
1821
+ Set rational to False to skip rational algorithm. By default it is set
1822
+ to True.
1823
+ full : {True, False}, optional
1824
+ Set full to True to increase the range of rational algorithm.
1825
+ See :func:`rational_algorithm` for details. By default it is set to
1826
+ False.
1827
+
1828
+ Examples
1829
+ ========
1830
+
1831
+ >>> from sympy import fps, ln, atan, sin
1832
+ >>> from sympy.abc import x, n
1833
+
1834
+ Rational Functions
1835
+
1836
+ >>> fps(ln(1 + x)).truncate()
1837
+ x - x**2/2 + x**3/3 - x**4/4 + x**5/5 + O(x**6)
1838
+
1839
+ >>> fps(atan(x), full=True).truncate()
1840
+ x - x**3/3 + x**5/5 + O(x**6)
1841
+
1842
+ Symbolic Functions
1843
+
1844
+ >>> fps(x**n*sin(x**2), x).truncate(8)
1845
+ -x**(n + 6)/6 + x**(n + 2) + O(x**(n + 8))
1846
+
1847
+ See Also
1848
+ ========
1849
+
1850
+ sympy.series.formal.FormalPowerSeries
1851
+ sympy.series.formal.compute_fps
1852
+ """
1853
+ f = sympify(f)
1854
+
1855
+ if x is None:
1856
+ free = f.free_symbols
1857
+ if len(free) == 1:
1858
+ x = free.pop()
1859
+ elif not free:
1860
+ return f
1861
+ else:
1862
+ raise NotImplementedError("multivariate formal power series")
1863
+
1864
+ result = compute_fps(f, x, x0, dir, hyper, order, rational, full)
1865
+
1866
+ if result is None:
1867
+ return f
1868
+
1869
+ return FormalPowerSeries(f, x, x0, dir, result)
evalkit_internvl/lib/python3.10/site-packages/sympy/series/fourier.py ADDED
@@ -0,0 +1,811 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """Fourier Series"""
2
+
3
+ from sympy.core.numbers import (oo, pi)
4
+ from sympy.core.symbol import Wild
5
+ from sympy.core.expr import Expr
6
+ from sympy.core.add import Add
7
+ from sympy.core.containers import Tuple
8
+ from sympy.core.singleton import S
9
+ from sympy.core.symbol import Dummy, Symbol
10
+ from sympy.core.sympify import sympify
11
+ from sympy.functions.elementary.trigonometric import sin, cos, sinc
12
+ from sympy.series.series_class import SeriesBase
13
+ from sympy.series.sequences import SeqFormula
14
+ from sympy.sets.sets import Interval
15
+ from sympy.utilities.iterables import is_sequence
16
+
17
+
18
+ __doctest_requires__ = {('fourier_series',): ['matplotlib']}
19
+
20
+
21
+ def fourier_cos_seq(func, limits, n):
22
+ """Returns the cos sequence in a Fourier series"""
23
+ from sympy.integrals import integrate
24
+ x, L = limits[0], limits[2] - limits[1]
25
+ cos_term = cos(2*n*pi*x / L)
26
+ formula = 2 * cos_term * integrate(func * cos_term, limits) / L
27
+ a0 = formula.subs(n, S.Zero) / 2
28
+ return a0, SeqFormula(2 * cos_term * integrate(func * cos_term, limits)
29
+ / L, (n, 1, oo))
30
+
31
+
32
+ def fourier_sin_seq(func, limits, n):
33
+ """Returns the sin sequence in a Fourier series"""
34
+ from sympy.integrals import integrate
35
+ x, L = limits[0], limits[2] - limits[1]
36
+ sin_term = sin(2*n*pi*x / L)
37
+ return SeqFormula(2 * sin_term * integrate(func * sin_term, limits)
38
+ / L, (n, 1, oo))
39
+
40
+
41
+ def _process_limits(func, limits):
42
+ """
43
+ Limits should be of the form (x, start, stop).
44
+ x should be a symbol. Both start and stop should be bounded.
45
+
46
+ Explanation
47
+ ===========
48
+
49
+ * If x is not given, x is determined from func.
50
+ * If limits is None. Limit of the form (x, -pi, pi) is returned.
51
+
52
+ Examples
53
+ ========
54
+
55
+ >>> from sympy.series.fourier import _process_limits as pari
56
+ >>> from sympy.abc import x
57
+ >>> pari(x**2, (x, -2, 2))
58
+ (x, -2, 2)
59
+ >>> pari(x**2, (-2, 2))
60
+ (x, -2, 2)
61
+ >>> pari(x**2, None)
62
+ (x, -pi, pi)
63
+ """
64
+ def _find_x(func):
65
+ free = func.free_symbols
66
+ if len(free) == 1:
67
+ return free.pop()
68
+ elif not free:
69
+ return Dummy('k')
70
+ else:
71
+ raise ValueError(
72
+ " specify dummy variables for %s. If the function contains"
73
+ " more than one free symbol, a dummy variable should be"
74
+ " supplied explicitly e.g. FourierSeries(m*n**2, (n, -pi, pi))"
75
+ % func)
76
+
77
+ x, start, stop = None, None, None
78
+ if limits is None:
79
+ x, start, stop = _find_x(func), -pi, pi
80
+ if is_sequence(limits, Tuple):
81
+ if len(limits) == 3:
82
+ x, start, stop = limits
83
+ elif len(limits) == 2:
84
+ x = _find_x(func)
85
+ start, stop = limits
86
+
87
+ if not isinstance(x, Symbol) or start is None or stop is None:
88
+ raise ValueError('Invalid limits given: %s' % str(limits))
89
+
90
+ unbounded = [S.NegativeInfinity, S.Infinity]
91
+ if start in unbounded or stop in unbounded:
92
+ raise ValueError("Both the start and end value should be bounded")
93
+
94
+ return sympify((x, start, stop))
95
+
96
+
97
+ def finite_check(f, x, L):
98
+
99
+ def check_fx(exprs, x):
100
+ return x not in exprs.free_symbols
101
+
102
+ def check_sincos(_expr, x, L):
103
+ if isinstance(_expr, (sin, cos)):
104
+ sincos_args = _expr.args[0]
105
+
106
+ if sincos_args.match(a*(pi/L)*x + b) is not None:
107
+ return True
108
+ else:
109
+ return False
110
+
111
+ from sympy.simplify.fu import TR2, TR1, sincos_to_sum
112
+ _expr = sincos_to_sum(TR2(TR1(f)))
113
+ add_coeff = _expr.as_coeff_add()
114
+
115
+ a = Wild('a', properties=[lambda k: k.is_Integer, lambda k: k != S.Zero, ])
116
+ b = Wild('b', properties=[lambda k: x not in k.free_symbols, ])
117
+
118
+ for s in add_coeff[1]:
119
+ mul_coeffs = s.as_coeff_mul()[1]
120
+ for t in mul_coeffs:
121
+ if not (check_fx(t, x) or check_sincos(t, x, L)):
122
+ return False, f
123
+
124
+ return True, _expr
125
+
126
+
127
+ class FourierSeries(SeriesBase):
128
+ r"""Represents Fourier sine/cosine series.
129
+
130
+ Explanation
131
+ ===========
132
+
133
+ This class only represents a fourier series.
134
+ No computation is performed.
135
+
136
+ For how to compute Fourier series, see the :func:`fourier_series`
137
+ docstring.
138
+
139
+ See Also
140
+ ========
141
+
142
+ sympy.series.fourier.fourier_series
143
+ """
144
+ def __new__(cls, *args):
145
+ args = map(sympify, args)
146
+ return Expr.__new__(cls, *args)
147
+
148
+ @property
149
+ def function(self):
150
+ return self.args[0]
151
+
152
+ @property
153
+ def x(self):
154
+ return self.args[1][0]
155
+
156
+ @property
157
+ def period(self):
158
+ return (self.args[1][1], self.args[1][2])
159
+
160
+ @property
161
+ def a0(self):
162
+ return self.args[2][0]
163
+
164
+ @property
165
+ def an(self):
166
+ return self.args[2][1]
167
+
168
+ @property
169
+ def bn(self):
170
+ return self.args[2][2]
171
+
172
+ @property
173
+ def interval(self):
174
+ return Interval(0, oo)
175
+
176
+ @property
177
+ def start(self):
178
+ return self.interval.inf
179
+
180
+ @property
181
+ def stop(self):
182
+ return self.interval.sup
183
+
184
+ @property
185
+ def length(self):
186
+ return oo
187
+
188
+ @property
189
+ def L(self):
190
+ return abs(self.period[1] - self.period[0]) / 2
191
+
192
+ def _eval_subs(self, old, new):
193
+ x = self.x
194
+ if old.has(x):
195
+ return self
196
+
197
+ def truncate(self, n=3):
198
+ """
199
+ Return the first n nonzero terms of the series.
200
+
201
+ If ``n`` is None return an iterator.
202
+
203
+ Parameters
204
+ ==========
205
+
206
+ n : int or None
207
+ Amount of non-zero terms in approximation or None.
208
+
209
+ Returns
210
+ =======
211
+
212
+ Expr or iterator :
213
+ Approximation of function expanded into Fourier series.
214
+
215
+ Examples
216
+ ========
217
+
218
+ >>> from sympy import fourier_series, pi
219
+ >>> from sympy.abc import x
220
+ >>> s = fourier_series(x, (x, -pi, pi))
221
+ >>> s.truncate(4)
222
+ 2*sin(x) - sin(2*x) + 2*sin(3*x)/3 - sin(4*x)/2
223
+
224
+ See Also
225
+ ========
226
+
227
+ sympy.series.fourier.FourierSeries.sigma_approximation
228
+ """
229
+ if n is None:
230
+ return iter(self)
231
+
232
+ terms = []
233
+ for t in self:
234
+ if len(terms) == n:
235
+ break
236
+ if t is not S.Zero:
237
+ terms.append(t)
238
+
239
+ return Add(*terms)
240
+
241
+ def sigma_approximation(self, n=3):
242
+ r"""
243
+ Return :math:`\sigma`-approximation of Fourier series with respect
244
+ to order n.
245
+
246
+ Explanation
247
+ ===========
248
+
249
+ Sigma approximation adjusts a Fourier summation to eliminate the Gibbs
250
+ phenomenon which would otherwise occur at discontinuities.
251
+ A sigma-approximated summation for a Fourier series of a T-periodical
252
+ function can be written as
253
+
254
+ .. math::
255
+ s(\theta) = \frac{1}{2} a_0 + \sum _{k=1}^{m-1}
256
+ \operatorname{sinc} \Bigl( \frac{k}{m} \Bigr) \cdot
257
+ \left[ a_k \cos \Bigl( \frac{2\pi k}{T} \theta \Bigr)
258
+ + b_k \sin \Bigl( \frac{2\pi k}{T} \theta \Bigr) \right],
259
+
260
+ where :math:`a_0, a_k, b_k, k=1,\ldots,{m-1}` are standard Fourier
261
+ series coefficients and
262
+ :math:`\operatorname{sinc} \Bigl( \frac{k}{m} \Bigr)` is a Lanczos
263
+ :math:`\sigma` factor (expressed in terms of normalized
264
+ :math:`\operatorname{sinc}` function).
265
+
266
+ Parameters
267
+ ==========
268
+
269
+ n : int
270
+ Highest order of the terms taken into account in approximation.
271
+
272
+ Returns
273
+ =======
274
+
275
+ Expr :
276
+ Sigma approximation of function expanded into Fourier series.
277
+
278
+ Examples
279
+ ========
280
+
281
+ >>> from sympy import fourier_series, pi
282
+ >>> from sympy.abc import x
283
+ >>> s = fourier_series(x, (x, -pi, pi))
284
+ >>> s.sigma_approximation(4)
285
+ 2*sin(x)*sinc(pi/4) - 2*sin(2*x)/pi + 2*sin(3*x)*sinc(3*pi/4)/3
286
+
287
+ See Also
288
+ ========
289
+
290
+ sympy.series.fourier.FourierSeries.truncate
291
+
292
+ Notes
293
+ =====
294
+
295
+ The behaviour of
296
+ :meth:`~sympy.series.fourier.FourierSeries.sigma_approximation`
297
+ is different from :meth:`~sympy.series.fourier.FourierSeries.truncate`
298
+ - it takes all nonzero terms of degree smaller than n, rather than
299
+ first n nonzero ones.
300
+
301
+ References
302
+ ==========
303
+
304
+ .. [1] https://en.wikipedia.org/wiki/Gibbs_phenomenon
305
+ .. [2] https://en.wikipedia.org/wiki/Sigma_approximation
306
+ """
307
+ terms = [sinc(pi * i / n) * t for i, t in enumerate(self[:n])
308
+ if t is not S.Zero]
309
+ return Add(*terms)
310
+
311
+ def shift(self, s):
312
+ """
313
+ Shift the function by a term independent of x.
314
+
315
+ Explanation
316
+ ===========
317
+
318
+ f(x) -> f(x) + s
319
+
320
+ This is fast, if Fourier series of f(x) is already
321
+ computed.
322
+
323
+ Examples
324
+ ========
325
+
326
+ >>> from sympy import fourier_series, pi
327
+ >>> from sympy.abc import x
328
+ >>> s = fourier_series(x**2, (x, -pi, pi))
329
+ >>> s.shift(1).truncate()
330
+ -4*cos(x) + cos(2*x) + 1 + pi**2/3
331
+ """
332
+ s, x = sympify(s), self.x
333
+
334
+ if x in s.free_symbols:
335
+ raise ValueError("'%s' should be independent of %s" % (s, x))
336
+
337
+ a0 = self.a0 + s
338
+ sfunc = self.function + s
339
+
340
+ return self.func(sfunc, self.args[1], (a0, self.an, self.bn))
341
+
342
+ def shiftx(self, s):
343
+ """
344
+ Shift x by a term independent of x.
345
+
346
+ Explanation
347
+ ===========
348
+
349
+ f(x) -> f(x + s)
350
+
351
+ This is fast, if Fourier series of f(x) is already
352
+ computed.
353
+
354
+ Examples
355
+ ========
356
+
357
+ >>> from sympy import fourier_series, pi
358
+ >>> from sympy.abc import x
359
+ >>> s = fourier_series(x**2, (x, -pi, pi))
360
+ >>> s.shiftx(1).truncate()
361
+ -4*cos(x + 1) + cos(2*x + 2) + pi**2/3
362
+ """
363
+ s, x = sympify(s), self.x
364
+
365
+ if x in s.free_symbols:
366
+ raise ValueError("'%s' should be independent of %s" % (s, x))
367
+
368
+ an = self.an.subs(x, x + s)
369
+ bn = self.bn.subs(x, x + s)
370
+ sfunc = self.function.subs(x, x + s)
371
+
372
+ return self.func(sfunc, self.args[1], (self.a0, an, bn))
373
+
374
+ def scale(self, s):
375
+ """
376
+ Scale the function by a term independent of x.
377
+
378
+ Explanation
379
+ ===========
380
+
381
+ f(x) -> s * f(x)
382
+
383
+ This is fast, if Fourier series of f(x) is already
384
+ computed.
385
+
386
+ Examples
387
+ ========
388
+
389
+ >>> from sympy import fourier_series, pi
390
+ >>> from sympy.abc import x
391
+ >>> s = fourier_series(x**2, (x, -pi, pi))
392
+ >>> s.scale(2).truncate()
393
+ -8*cos(x) + 2*cos(2*x) + 2*pi**2/3
394
+ """
395
+ s, x = sympify(s), self.x
396
+
397
+ if x in s.free_symbols:
398
+ raise ValueError("'%s' should be independent of %s" % (s, x))
399
+
400
+ an = self.an.coeff_mul(s)
401
+ bn = self.bn.coeff_mul(s)
402
+ a0 = self.a0 * s
403
+ sfunc = self.args[0] * s
404
+
405
+ return self.func(sfunc, self.args[1], (a0, an, bn))
406
+
407
+ def scalex(self, s):
408
+ """
409
+ Scale x by a term independent of x.
410
+
411
+ Explanation
412
+ ===========
413
+
414
+ f(x) -> f(s*x)
415
+
416
+ This is fast, if Fourier series of f(x) is already
417
+ computed.
418
+
419
+ Examples
420
+ ========
421
+
422
+ >>> from sympy import fourier_series, pi
423
+ >>> from sympy.abc import x
424
+ >>> s = fourier_series(x**2, (x, -pi, pi))
425
+ >>> s.scalex(2).truncate()
426
+ -4*cos(2*x) + cos(4*x) + pi**2/3
427
+ """
428
+ s, x = sympify(s), self.x
429
+
430
+ if x in s.free_symbols:
431
+ raise ValueError("'%s' should be independent of %s" % (s, x))
432
+
433
+ an = self.an.subs(x, x * s)
434
+ bn = self.bn.subs(x, x * s)
435
+ sfunc = self.function.subs(x, x * s)
436
+
437
+ return self.func(sfunc, self.args[1], (self.a0, an, bn))
438
+
439
+ def _eval_as_leading_term(self, x, logx=None, cdir=0):
440
+ for t in self:
441
+ if t is not S.Zero:
442
+ return t
443
+
444
+ def _eval_term(self, pt):
445
+ if pt == 0:
446
+ return self.a0
447
+ return self.an.coeff(pt) + self.bn.coeff(pt)
448
+
449
+ def __neg__(self):
450
+ return self.scale(-1)
451
+
452
+ def __add__(self, other):
453
+ if isinstance(other, FourierSeries):
454
+ if self.period != other.period:
455
+ raise ValueError("Both the series should have same periods")
456
+
457
+ x, y = self.x, other.x
458
+ function = self.function + other.function.subs(y, x)
459
+
460
+ if self.x not in function.free_symbols:
461
+ return function
462
+
463
+ an = self.an + other.an
464
+ bn = self.bn + other.bn
465
+ a0 = self.a0 + other.a0
466
+
467
+ return self.func(function, self.args[1], (a0, an, bn))
468
+
469
+ return Add(self, other)
470
+
471
+ def __sub__(self, other):
472
+ return self.__add__(-other)
473
+
474
+
475
+ class FiniteFourierSeries(FourierSeries):
476
+ r"""Represents Finite Fourier sine/cosine series.
477
+
478
+ For how to compute Fourier series, see the :func:`fourier_series`
479
+ docstring.
480
+
481
+ Parameters
482
+ ==========
483
+
484
+ f : Expr
485
+ Expression for finding fourier_series
486
+
487
+ limits : ( x, start, stop)
488
+ x is the independent variable for the expression f
489
+ (start, stop) is the period of the fourier series
490
+
491
+ exprs: (a0, an, bn) or Expr
492
+ a0 is the constant term a0 of the fourier series
493
+ an is a dictionary of coefficients of cos terms
494
+ an[k] = coefficient of cos(pi*(k/L)*x)
495
+ bn is a dictionary of coefficients of sin terms
496
+ bn[k] = coefficient of sin(pi*(k/L)*x)
497
+
498
+ or exprs can be an expression to be converted to fourier form
499
+
500
+ Methods
501
+ =======
502
+
503
+ This class is an extension of FourierSeries class.
504
+ Please refer to sympy.series.fourier.FourierSeries for
505
+ further information.
506
+
507
+ See Also
508
+ ========
509
+
510
+ sympy.series.fourier.FourierSeries
511
+ sympy.series.fourier.fourier_series
512
+ """
513
+
514
+ def __new__(cls, f, limits, exprs):
515
+ f = sympify(f)
516
+ limits = sympify(limits)
517
+ exprs = sympify(exprs)
518
+
519
+ if not (isinstance(exprs, Tuple) and len(exprs) == 3): # exprs is not of form (a0, an, bn)
520
+ # Converts the expression to fourier form
521
+ c, e = exprs.as_coeff_add()
522
+ from sympy.simplify.fu import TR10
523
+ rexpr = c + Add(*[TR10(i) for i in e])
524
+ a0, exp_ls = rexpr.expand(trig=False, power_base=False, power_exp=False, log=False).as_coeff_add()
525
+
526
+ x = limits[0]
527
+ L = abs(limits[2] - limits[1]) / 2
528
+
529
+ a = Wild('a', properties=[lambda k: k.is_Integer, lambda k: k is not S.Zero, ])
530
+ b = Wild('b', properties=[lambda k: x not in k.free_symbols, ])
531
+
532
+ an = {}
533
+ bn = {}
534
+
535
+ # separates the coefficients of sin and cos terms in dictionaries an, and bn
536
+ for p in exp_ls:
537
+ t = p.match(b * cos(a * (pi / L) * x))
538
+ q = p.match(b * sin(a * (pi / L) * x))
539
+ if t:
540
+ an[t[a]] = t[b] + an.get(t[a], S.Zero)
541
+ elif q:
542
+ bn[q[a]] = q[b] + bn.get(q[a], S.Zero)
543
+ else:
544
+ a0 += p
545
+
546
+ exprs = Tuple(a0, an, bn)
547
+
548
+ return Expr.__new__(cls, f, limits, exprs)
549
+
550
+ @property
551
+ def interval(self):
552
+ _length = 1 if self.a0 else 0
553
+ _length += max(set(self.an.keys()).union(set(self.bn.keys()))) + 1
554
+ return Interval(0, _length)
555
+
556
+ @property
557
+ def length(self):
558
+ return self.stop - self.start
559
+
560
+ def shiftx(self, s):
561
+ s, x = sympify(s), self.x
562
+
563
+ if x in s.free_symbols:
564
+ raise ValueError("'%s' should be independent of %s" % (s, x))
565
+
566
+ _expr = self.truncate().subs(x, x + s)
567
+ sfunc = self.function.subs(x, x + s)
568
+
569
+ return self.func(sfunc, self.args[1], _expr)
570
+
571
+ def scale(self, s):
572
+ s, x = sympify(s), self.x
573
+
574
+ if x in s.free_symbols:
575
+ raise ValueError("'%s' should be independent of %s" % (s, x))
576
+
577
+ _expr = self.truncate() * s
578
+ sfunc = self.function * s
579
+
580
+ return self.func(sfunc, self.args[1], _expr)
581
+
582
+ def scalex(self, s):
583
+ s, x = sympify(s), self.x
584
+
585
+ if x in s.free_symbols:
586
+ raise ValueError("'%s' should be independent of %s" % (s, x))
587
+
588
+ _expr = self.truncate().subs(x, x * s)
589
+ sfunc = self.function.subs(x, x * s)
590
+
591
+ return self.func(sfunc, self.args[1], _expr)
592
+
593
+ def _eval_term(self, pt):
594
+ if pt == 0:
595
+ return self.a0
596
+
597
+ _term = self.an.get(pt, S.Zero) * cos(pt * (pi / self.L) * self.x) \
598
+ + self.bn.get(pt, S.Zero) * sin(pt * (pi / self.L) * self.x)
599
+ return _term
600
+
601
+ def __add__(self, other):
602
+ if isinstance(other, FourierSeries):
603
+ return other.__add__(fourier_series(self.function, self.args[1],\
604
+ finite=False))
605
+ elif isinstance(other, FiniteFourierSeries):
606
+ if self.period != other.period:
607
+ raise ValueError("Both the series should have same periods")
608
+
609
+ x, y = self.x, other.x
610
+ function = self.function + other.function.subs(y, x)
611
+
612
+ if self.x not in function.free_symbols:
613
+ return function
614
+
615
+ return fourier_series(function, limits=self.args[1])
616
+
617
+
618
+ def fourier_series(f, limits=None, finite=True):
619
+ r"""Computes the Fourier trigonometric series expansion.
620
+
621
+ Explanation
622
+ ===========
623
+
624
+ Fourier trigonometric series of $f(x)$ over the interval $(a, b)$
625
+ is defined as:
626
+
627
+ .. math::
628
+ \frac{a_0}{2} + \sum_{n=1}^{\infty}
629
+ (a_n \cos(\frac{2n \pi x}{L}) + b_n \sin(\frac{2n \pi x}{L}))
630
+
631
+ where the coefficients are:
632
+
633
+ .. math::
634
+ L = b - a
635
+
636
+ .. math::
637
+ a_0 = \frac{2}{L} \int_{a}^{b}{f(x) dx}
638
+
639
+ .. math::
640
+ a_n = \frac{2}{L} \int_{a}^{b}{f(x) \cos(\frac{2n \pi x}{L}) dx}
641
+
642
+ .. math::
643
+ b_n = \frac{2}{L} \int_{a}^{b}{f(x) \sin(\frac{2n \pi x}{L}) dx}
644
+
645
+ The condition whether the function $f(x)$ given should be periodic
646
+ or not is more than necessary, because it is sufficient to consider
647
+ the series to be converging to $f(x)$ only in the given interval,
648
+ not throughout the whole real line.
649
+
650
+ This also brings a lot of ease for the computation because
651
+ you do not have to make $f(x)$ artificially periodic by
652
+ wrapping it with piecewise, modulo operations,
653
+ but you can shape the function to look like the desired periodic
654
+ function only in the interval $(a, b)$, and the computed series will
655
+ automatically become the series of the periodic version of $f(x)$.
656
+
657
+ This property is illustrated in the examples section below.
658
+
659
+ Parameters
660
+ ==========
661
+
662
+ limits : (sym, start, end), optional
663
+ *sym* denotes the symbol the series is computed with respect to.
664
+
665
+ *start* and *end* denotes the start and the end of the interval
666
+ where the fourier series converges to the given function.
667
+
668
+ Default range is specified as $-\pi$ and $\pi$.
669
+
670
+ Returns
671
+ =======
672
+
673
+ FourierSeries
674
+ A symbolic object representing the Fourier trigonometric series.
675
+
676
+ Examples
677
+ ========
678
+
679
+ Computing the Fourier series of $f(x) = x^2$:
680
+
681
+ >>> from sympy import fourier_series, pi
682
+ >>> from sympy.abc import x
683
+ >>> f = x**2
684
+ >>> s = fourier_series(f, (x, -pi, pi))
685
+ >>> s1 = s.truncate(n=3)
686
+ >>> s1
687
+ -4*cos(x) + cos(2*x) + pi**2/3
688
+
689
+ Shifting of the Fourier series:
690
+
691
+ >>> s.shift(1).truncate()
692
+ -4*cos(x) + cos(2*x) + 1 + pi**2/3
693
+ >>> s.shiftx(1).truncate()
694
+ -4*cos(x + 1) + cos(2*x + 2) + pi**2/3
695
+
696
+ Scaling of the Fourier series:
697
+
698
+ >>> s.scale(2).truncate()
699
+ -8*cos(x) + 2*cos(2*x) + 2*pi**2/3
700
+ >>> s.scalex(2).truncate()
701
+ -4*cos(2*x) + cos(4*x) + pi**2/3
702
+
703
+ Computing the Fourier series of $f(x) = x$:
704
+
705
+ This illustrates how truncating to the higher order gives better
706
+ convergence.
707
+
708
+ .. plot::
709
+ :context: reset
710
+ :format: doctest
711
+ :include-source: True
712
+
713
+ >>> from sympy import fourier_series, pi, plot
714
+ >>> from sympy.abc import x
715
+ >>> f = x
716
+ >>> s = fourier_series(f, (x, -pi, pi))
717
+ >>> s1 = s.truncate(n = 3)
718
+ >>> s2 = s.truncate(n = 5)
719
+ >>> s3 = s.truncate(n = 7)
720
+ >>> p = plot(f, s1, s2, s3, (x, -pi, pi), show=False, legend=True)
721
+
722
+ >>> p[0].line_color = (0, 0, 0)
723
+ >>> p[0].label = 'x'
724
+ >>> p[1].line_color = (0.7, 0.7, 0.7)
725
+ >>> p[1].label = 'n=3'
726
+ >>> p[2].line_color = (0.5, 0.5, 0.5)
727
+ >>> p[2].label = 'n=5'
728
+ >>> p[3].line_color = (0.3, 0.3, 0.3)
729
+ >>> p[3].label = 'n=7'
730
+
731
+ >>> p.show()
732
+
733
+ This illustrates how the series converges to different sawtooth
734
+ waves if the different ranges are specified.
735
+
736
+ .. plot::
737
+ :context: close-figs
738
+ :format: doctest
739
+ :include-source: True
740
+
741
+ >>> s1 = fourier_series(x, (x, -1, 1)).truncate(10)
742
+ >>> s2 = fourier_series(x, (x, -pi, pi)).truncate(10)
743
+ >>> s3 = fourier_series(x, (x, 0, 1)).truncate(10)
744
+ >>> p = plot(x, s1, s2, s3, (x, -5, 5), show=False, legend=True)
745
+
746
+ >>> p[0].line_color = (0, 0, 0)
747
+ >>> p[0].label = 'x'
748
+ >>> p[1].line_color = (0.7, 0.7, 0.7)
749
+ >>> p[1].label = '[-1, 1]'
750
+ >>> p[2].line_color = (0.5, 0.5, 0.5)
751
+ >>> p[2].label = '[-pi, pi]'
752
+ >>> p[3].line_color = (0.3, 0.3, 0.3)
753
+ >>> p[3].label = '[0, 1]'
754
+
755
+ >>> p.show()
756
+
757
+ Notes
758
+ =====
759
+
760
+ Computing Fourier series can be slow
761
+ due to the integration required in computing
762
+ an, bn.
763
+
764
+ It is faster to compute Fourier series of a function
765
+ by using shifting and scaling on an already
766
+ computed Fourier series rather than computing
767
+ again.
768
+
769
+ e.g. If the Fourier series of ``x**2`` is known
770
+ the Fourier series of ``x**2 - 1`` can be found by shifting by ``-1``.
771
+
772
+ See Also
773
+ ========
774
+
775
+ sympy.series.fourier.FourierSeries
776
+
777
+ References
778
+ ==========
779
+
780
+ .. [1] https://mathworld.wolfram.com/FourierSeries.html
781
+ """
782
+ f = sympify(f)
783
+
784
+ limits = _process_limits(f, limits)
785
+ x = limits[0]
786
+
787
+ if x not in f.free_symbols:
788
+ return f
789
+
790
+ if finite:
791
+ L = abs(limits[2] - limits[1]) / 2
792
+ is_finite, res_f = finite_check(f, x, L)
793
+ if is_finite:
794
+ return FiniteFourierSeries(f, limits, res_f)
795
+
796
+ n = Dummy('n')
797
+ center = (limits[1] + limits[2]) / 2
798
+ if center.is_zero:
799
+ neg_f = f.subs(x, -x)
800
+ if f == neg_f:
801
+ a0, an = fourier_cos_seq(f, limits, n)
802
+ bn = SeqFormula(0, (1, oo))
803
+ return FourierSeries(f, limits, (a0, an, bn))
804
+ elif f == -neg_f:
805
+ a0 = S.Zero
806
+ an = SeqFormula(0, (1, oo))
807
+ bn = fourier_sin_seq(f, limits, n)
808
+ return FourierSeries(f, limits, (a0, an, bn))
809
+ a0, an = fourier_cos_seq(f, limits, n)
810
+ bn = fourier_sin_seq(f, limits, n)
811
+ return FourierSeries(f, limits, (a0, an, bn))
evalkit_internvl/lib/python3.10/site-packages/sympy/series/gruntz.py ADDED
@@ -0,0 +1,739 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """
2
+ Limits
3
+ ======
4
+
5
+ Implemented according to the PhD thesis
6
+ https://www.cybertester.com/data/gruntz.pdf, which contains very thorough
7
+ descriptions of the algorithm including many examples. We summarize here
8
+ the gist of it.
9
+
10
+ All functions are sorted according to how rapidly varying they are at
11
+ infinity using the following rules. Any two functions f and g can be
12
+ compared using the properties of L:
13
+
14
+ L=lim log|f(x)| / log|g(x)| (for x -> oo)
15
+
16
+ We define >, < ~ according to::
17
+
18
+ 1. f > g .... L=+-oo
19
+
20
+ we say that:
21
+ - f is greater than any power of g
22
+ - f is more rapidly varying than g
23
+ - f goes to infinity/zero faster than g
24
+
25
+ 2. f < g .... L=0
26
+
27
+ we say that:
28
+ - f is lower than any power of g
29
+
30
+ 3. f ~ g .... L!=0, +-oo
31
+
32
+ we say that:
33
+ - both f and g are bounded from above and below by suitable integral
34
+ powers of the other
35
+
36
+ Examples
37
+ ========
38
+ ::
39
+ 2 < x < exp(x) < exp(x**2) < exp(exp(x))
40
+ 2 ~ 3 ~ -5
41
+ x ~ x**2 ~ x**3 ~ 1/x ~ x**m ~ -x
42
+ exp(x) ~ exp(-x) ~ exp(2x) ~ exp(x)**2 ~ exp(x+exp(-x))
43
+ f ~ 1/f
44
+
45
+ So we can divide all the functions into comparability classes (x and x^2
46
+ belong to one class, exp(x) and exp(-x) belong to some other class). In
47
+ principle, we could compare any two functions, but in our algorithm, we
48
+ do not compare anything below the class 2~3~-5 (for example log(x) is
49
+ below this), so we set 2~3~-5 as the lowest comparability class.
50
+
51
+ Given the function f, we find the list of most rapidly varying (mrv set)
52
+ subexpressions of it. This list belongs to the same comparability class.
53
+ Let's say it is {exp(x), exp(2x)}. Using the rule f ~ 1/f we find an
54
+ element "w" (either from the list or a new one) from the same
55
+ comparability class which goes to zero at infinity. In our example we
56
+ set w=exp(-x) (but we could also set w=exp(-2x) or w=exp(-3x) ...). We
57
+ rewrite the mrv set using w, in our case {1/w, 1/w^2}, and substitute it
58
+ into f. Then we expand f into a series in w::
59
+
60
+ f = c0*w^e0 + c1*w^e1 + ... + O(w^en), where e0<e1<...<en, c0!=0
61
+
62
+ but for x->oo, lim f = lim c0*w^e0, because all the other terms go to zero,
63
+ because w goes to zero faster than the ci and ei. So::
64
+
65
+ for e0>0, lim f = 0
66
+ for e0<0, lim f = +-oo (the sign depends on the sign of c0)
67
+ for e0=0, lim f = lim c0
68
+
69
+ We need to recursively compute limits at several places of the algorithm, but
70
+ as is shown in the PhD thesis, it always finishes.
71
+
72
+ Important functions from the implementation:
73
+
74
+ compare(a, b, x) compares "a" and "b" by computing the limit L.
75
+ mrv(e, x) returns list of most rapidly varying (mrv) subexpressions of "e"
76
+ rewrite(e, Omega, x, wsym) rewrites "e" in terms of w
77
+ leadterm(f, x) returns the lowest power term in the series of f
78
+ mrv_leadterm(e, x) returns the lead term (c0, e0) for e
79
+ limitinf(e, x) computes lim e (for x->oo)
80
+ limit(e, z, z0) computes any limit by converting it to the case x->oo
81
+
82
+ All the functions are really simple and straightforward except
83
+ rewrite(), which is the most difficult/complex part of the algorithm.
84
+ When the algorithm fails, the bugs are usually in the series expansion
85
+ (i.e. in SymPy) or in rewrite.
86
+
87
+ This code is almost exact rewrite of the Maple code inside the Gruntz
88
+ thesis.
89
+
90
+ Debugging
91
+ ---------
92
+
93
+ Because the gruntz algorithm is highly recursive, it's difficult to
94
+ figure out what went wrong inside a debugger. Instead, turn on nice
95
+ debug prints by defining the environment variable SYMPY_DEBUG. For
96
+ example:
97
+
98
+ [user@localhost]: SYMPY_DEBUG=True ./bin/isympy
99
+
100
+ In [1]: limit(sin(x)/x, x, 0)
101
+ limitinf(_x*sin(1/_x), _x) = 1
102
+ +-mrv_leadterm(_x*sin(1/_x), _x) = (1, 0)
103
+ | +-mrv(_x*sin(1/_x), _x) = set([_x])
104
+ | | +-mrv(_x, _x) = set([_x])
105
+ | | +-mrv(sin(1/_x), _x) = set([_x])
106
+ | | +-mrv(1/_x, _x) = set([_x])
107
+ | | +-mrv(_x, _x) = set([_x])
108
+ | +-mrv_leadterm(exp(_x)*sin(exp(-_x)), _x, set([exp(_x)])) = (1, 0)
109
+ | +-rewrite(exp(_x)*sin(exp(-_x)), set([exp(_x)]), _x, _w) = (1/_w*sin(_w), -_x)
110
+ | +-sign(_x, _x) = 1
111
+ | +-mrv_leadterm(1, _x) = (1, 0)
112
+ +-sign(0, _x) = 0
113
+ +-limitinf(1, _x) = 1
114
+
115
+ And check manually which line is wrong. Then go to the source code and
116
+ debug this function to figure out the exact problem.
117
+
118
+ """
119
+ from functools import reduce
120
+
121
+ from sympy.core import Basic, S, Mul, PoleError, expand_mul
122
+ from sympy.core.cache import cacheit
123
+ from sympy.core.intfunc import ilcm
124
+ from sympy.core.numbers import I, oo
125
+ from sympy.core.symbol import Dummy, Wild
126
+ from sympy.core.traversal import bottom_up
127
+
128
+ from sympy.functions import log, exp, sign as _sign
129
+ from sympy.series.order import Order
130
+ from sympy.utilities.exceptions import SymPyDeprecationWarning
131
+ from sympy.utilities.misc import debug_decorator as debug
132
+ from sympy.utilities.timeutils import timethis
133
+
134
+ timeit = timethis('gruntz')
135
+
136
+
137
+ def compare(a, b, x):
138
+ """Returns "<" if a<b, "=" for a == b, ">" for a>b"""
139
+ # log(exp(...)) must always be simplified here for termination
140
+ la, lb = log(a), log(b)
141
+ if isinstance(a, Basic) and (isinstance(a, exp) or (a.is_Pow and a.base == S.Exp1)):
142
+ la = a.exp
143
+ if isinstance(b, Basic) and (isinstance(b, exp) or (b.is_Pow and b.base == S.Exp1)):
144
+ lb = b.exp
145
+
146
+ c = limitinf(la/lb, x)
147
+ if c == 0:
148
+ return "<"
149
+ elif c.is_infinite:
150
+ return ">"
151
+ else:
152
+ return "="
153
+
154
+
155
+ class SubsSet(dict):
156
+ """
157
+ Stores (expr, dummy) pairs, and how to rewrite expr-s.
158
+
159
+ Explanation
160
+ ===========
161
+
162
+ The gruntz algorithm needs to rewrite certain expressions in term of a new
163
+ variable w. We cannot use subs, because it is just too smart for us. For
164
+ example::
165
+
166
+ > Omega=[exp(exp(_p - exp(-_p))/(1 - 1/_p)), exp(exp(_p))]
167
+ > O2=[exp(-exp(_p) + exp(-exp(-_p))*exp(_p)/(1 - 1/_p))/_w, 1/_w]
168
+ > e = exp(exp(_p - exp(-_p))/(1 - 1/_p)) - exp(exp(_p))
169
+ > e.subs(Omega[0],O2[0]).subs(Omega[1],O2[1])
170
+ -1/w + exp(exp(p)*exp(-exp(-p))/(1 - 1/p))
171
+
172
+ is really not what we want!
173
+
174
+ So we do it the hard way and keep track of all the things we potentially
175
+ want to substitute by dummy variables. Consider the expression::
176
+
177
+ exp(x - exp(-x)) + exp(x) + x.
178
+
179
+ The mrv set is {exp(x), exp(-x), exp(x - exp(-x))}.
180
+ We introduce corresponding dummy variables d1, d2, d3 and rewrite::
181
+
182
+ d3 + d1 + x.
183
+
184
+ This class first of all keeps track of the mapping expr->variable, i.e.
185
+ will at this stage be a dictionary::
186
+
187
+ {exp(x): d1, exp(-x): d2, exp(x - exp(-x)): d3}.
188
+
189
+ [It turns out to be more convenient this way round.]
190
+ But sometimes expressions in the mrv set have other expressions from the
191
+ mrv set as subexpressions, and we need to keep track of that as well. In
192
+ this case, d3 is really exp(x - d2), so rewrites at this stage is::
193
+
194
+ {d3: exp(x-d2)}.
195
+
196
+ The function rewrite uses all this information to correctly rewrite our
197
+ expression in terms of w. In this case w can be chosen to be exp(-x),
198
+ i.e. d2. The correct rewriting then is::
199
+
200
+ exp(-w)/w + 1/w + x.
201
+ """
202
+ def __init__(self):
203
+ self.rewrites = {}
204
+
205
+ def __repr__(self):
206
+ return super().__repr__() + ', ' + self.rewrites.__repr__()
207
+
208
+ def __getitem__(self, key):
209
+ if key not in self:
210
+ self[key] = Dummy()
211
+ return dict.__getitem__(self, key)
212
+
213
+ def do_subs(self, e):
214
+ """Substitute the variables with expressions"""
215
+ for expr, var in self.items():
216
+ e = e.xreplace({var: expr})
217
+ return e
218
+
219
+ def meets(self, s2):
220
+ """Tell whether or not self and s2 have non-empty intersection"""
221
+ return set(self.keys()).intersection(list(s2.keys())) != set()
222
+
223
+ def union(self, s2, exps=None):
224
+ """Compute the union of self and s2, adjusting exps"""
225
+ res = self.copy()
226
+ tr = {}
227
+ for expr, var in s2.items():
228
+ if expr in self:
229
+ if exps:
230
+ exps = exps.xreplace({var: res[expr]})
231
+ tr[var] = res[expr]
232
+ else:
233
+ res[expr] = var
234
+ for var, rewr in s2.rewrites.items():
235
+ res.rewrites[var] = rewr.xreplace(tr)
236
+ return res, exps
237
+
238
+ def copy(self):
239
+ """Create a shallow copy of SubsSet"""
240
+ r = SubsSet()
241
+ r.rewrites = self.rewrites.copy()
242
+ for expr, var in self.items():
243
+ r[expr] = var
244
+ return r
245
+
246
+
247
+ @debug
248
+ def mrv(e, x):
249
+ """Returns a SubsSet of most rapidly varying (mrv) subexpressions of 'e',
250
+ and e rewritten in terms of these"""
251
+ from sympy.simplify.powsimp import powsimp
252
+ e = powsimp(e, deep=True, combine='exp')
253
+ if not isinstance(e, Basic):
254
+ raise TypeError("e should be an instance of Basic")
255
+ if not e.has(x):
256
+ return SubsSet(), e
257
+ elif e == x:
258
+ s = SubsSet()
259
+ return s, s[x]
260
+ elif e.is_Mul or e.is_Add:
261
+ i, d = e.as_independent(x) # throw away x-independent terms
262
+ if d.func != e.func:
263
+ s, expr = mrv(d, x)
264
+ return s, e.func(i, expr)
265
+ a, b = d.as_two_terms()
266
+ s1, e1 = mrv(a, x)
267
+ s2, e2 = mrv(b, x)
268
+ return mrv_max1(s1, s2, e.func(i, e1, e2), x)
269
+ elif e.is_Pow and e.base != S.Exp1:
270
+ e1 = S.One
271
+ while e.is_Pow:
272
+ b1 = e.base
273
+ e1 *= e.exp
274
+ e = b1
275
+ if b1 == 1:
276
+ return SubsSet(), b1
277
+ if e1.has(x):
278
+ if limitinf(b1, x) is S.One:
279
+ if limitinf(e1, x).is_infinite is False:
280
+ return mrv(exp(e1*(b1 - 1)), x)
281
+ return mrv(exp(e1*log(b1)), x)
282
+ else:
283
+ s, expr = mrv(b1, x)
284
+ return s, expr**e1
285
+ elif isinstance(e, log):
286
+ s, expr = mrv(e.args[0], x)
287
+ return s, log(expr)
288
+ elif isinstance(e, exp) or (e.is_Pow and e.base == S.Exp1):
289
+ # We know from the theory of this algorithm that exp(log(...)) may always
290
+ # be simplified here, and doing so is vital for termination.
291
+ if isinstance(e.exp, log):
292
+ return mrv(e.exp.args[0], x)
293
+ # if a product has an infinite factor the result will be
294
+ # infinite if there is no zero, otherwise NaN; here, we
295
+ # consider the result infinite if any factor is infinite
296
+ li = limitinf(e.exp, x)
297
+ if any(_.is_infinite for _ in Mul.make_args(li)):
298
+ s1 = SubsSet()
299
+ e1 = s1[e]
300
+ s2, e2 = mrv(e.exp, x)
301
+ su = s1.union(s2)[0]
302
+ su.rewrites[e1] = exp(e2)
303
+ return mrv_max3(s1, e1, s2, exp(e2), su, e1, x)
304
+ else:
305
+ s, expr = mrv(e.exp, x)
306
+ return s, exp(expr)
307
+ elif e.is_Function:
308
+ l = [mrv(a, x) for a in e.args]
309
+ l2 = [s for (s, _) in l if s != SubsSet()]
310
+ if len(l2) != 1:
311
+ # e.g. something like BesselJ(x, x)
312
+ raise NotImplementedError("MRV set computation for functions in"
313
+ " several variables not implemented.")
314
+ s, ss = l2[0], SubsSet()
315
+ args = [ss.do_subs(x[1]) for x in l]
316
+ return s, e.func(*args)
317
+ elif e.is_Derivative:
318
+ raise NotImplementedError("MRV set computation for derivatives"
319
+ " not implemented yet.")
320
+ raise NotImplementedError(
321
+ "Don't know how to calculate the mrv of '%s'" % e)
322
+
323
+
324
+ def mrv_max3(f, expsf, g, expsg, union, expsboth, x):
325
+ """
326
+ Computes the maximum of two sets of expressions f and g, which
327
+ are in the same comparability class, i.e. max() compares (two elements of)
328
+ f and g and returns either (f, expsf) [if f is larger], (g, expsg)
329
+ [if g is larger] or (union, expsboth) [if f, g are of the same class].
330
+ """
331
+ if not isinstance(f, SubsSet):
332
+ raise TypeError("f should be an instance of SubsSet")
333
+ if not isinstance(g, SubsSet):
334
+ raise TypeError("g should be an instance of SubsSet")
335
+ if f == SubsSet():
336
+ return g, expsg
337
+ elif g == SubsSet():
338
+ return f, expsf
339
+ elif f.meets(g):
340
+ return union, expsboth
341
+
342
+ c = compare(list(f.keys())[0], list(g.keys())[0], x)
343
+ if c == ">":
344
+ return f, expsf
345
+ elif c == "<":
346
+ return g, expsg
347
+ else:
348
+ if c != "=":
349
+ raise ValueError("c should be =")
350
+ return union, expsboth
351
+
352
+
353
+ def mrv_max1(f, g, exps, x):
354
+ """Computes the maximum of two sets of expressions f and g, which
355
+ are in the same comparability class, i.e. mrv_max1() compares (two elements of)
356
+ f and g and returns the set, which is in the higher comparability class
357
+ of the union of both, if they have the same order of variation.
358
+ Also returns exps, with the appropriate substitutions made.
359
+ """
360
+ u, b = f.union(g, exps)
361
+ return mrv_max3(f, g.do_subs(exps), g, f.do_subs(exps),
362
+ u, b, x)
363
+
364
+
365
+ @debug
366
+ @cacheit
367
+ @timeit
368
+ def sign(e, x):
369
+ """
370
+ Returns a sign of an expression e(x) for x->oo.
371
+
372
+ ::
373
+
374
+ e > 0 for x sufficiently large ... 1
375
+ e == 0 for x sufficiently large ... 0
376
+ e < 0 for x sufficiently large ... -1
377
+
378
+ The result of this function is currently undefined if e changes sign
379
+ arbitrarily often for arbitrarily large x (e.g. sin(x)).
380
+
381
+ Note that this returns zero only if e is *constantly* zero
382
+ for x sufficiently large. [If e is constant, of course, this is just
383
+ the same thing as the sign of e.]
384
+ """
385
+ if not isinstance(e, Basic):
386
+ raise TypeError("e should be an instance of Basic")
387
+
388
+ if e.is_positive:
389
+ return 1
390
+ elif e.is_negative:
391
+ return -1
392
+ elif e.is_zero:
393
+ return 0
394
+
395
+ elif not e.has(x):
396
+ from sympy.simplify import logcombine
397
+ e = logcombine(e)
398
+ return _sign(e)
399
+ elif e == x:
400
+ return 1
401
+ elif e.is_Mul:
402
+ a, b = e.as_two_terms()
403
+ sa = sign(a, x)
404
+ if not sa:
405
+ return 0
406
+ return sa * sign(b, x)
407
+ elif isinstance(e, exp):
408
+ return 1
409
+ elif e.is_Pow:
410
+ if e.base == S.Exp1:
411
+ return 1
412
+ s = sign(e.base, x)
413
+ if s == 1:
414
+ return 1
415
+ if e.exp.is_Integer:
416
+ return s**e.exp
417
+ elif isinstance(e, log):
418
+ return sign(e.args[0] - 1, x)
419
+
420
+ # if all else fails, do it the hard way
421
+ c0, e0 = mrv_leadterm(e, x)
422
+ return sign(c0, x)
423
+
424
+
425
+ @debug
426
+ @timeit
427
+ @cacheit
428
+ def limitinf(e, x):
429
+ """Limit e(x) for x-> oo."""
430
+ # rewrite e in terms of tractable functions only
431
+
432
+ old = e
433
+ if not e.has(x):
434
+ return e # e is a constant
435
+ from sympy.simplify.powsimp import powdenest
436
+ from sympy.calculus.util import AccumBounds
437
+ if e.has(Order):
438
+ e = e.expand().removeO()
439
+ if not x.is_positive or x.is_integer:
440
+ # We make sure that x.is_positive is True and x.is_integer is None
441
+ # so we get all the correct mathematical behavior from the expression.
442
+ # We need a fresh variable.
443
+ p = Dummy('p', positive=True)
444
+ e = e.subs(x, p)
445
+ x = p
446
+ e = e.rewrite('tractable', deep=True, limitvar=x)
447
+ e = powdenest(e)
448
+ if isinstance(e, AccumBounds):
449
+ if mrv_leadterm(e.min, x) != mrv_leadterm(e.max, x):
450
+ raise NotImplementedError
451
+ c0, e0 = mrv_leadterm(e.min, x)
452
+ else:
453
+ c0, e0 = mrv_leadterm(e, x)
454
+ sig = sign(e0, x)
455
+ if sig == 1:
456
+ return S.Zero # e0>0: lim f = 0
457
+ elif sig == -1: # e0<0: lim f = +-oo (the sign depends on the sign of c0)
458
+ if c0.match(I*Wild("a", exclude=[I])):
459
+ return c0*oo
460
+ s = sign(c0, x)
461
+ # the leading term shouldn't be 0:
462
+ if s == 0:
463
+ raise ValueError("Leading term should not be 0")
464
+ return s*oo
465
+ elif sig == 0:
466
+ if c0 == old:
467
+ c0 = c0.cancel()
468
+ return limitinf(c0, x) # e0=0: lim f = lim c0
469
+ else:
470
+ raise ValueError("{} could not be evaluated".format(sig))
471
+
472
+
473
+ def moveup2(s, x):
474
+ r = SubsSet()
475
+ for expr, var in s.items():
476
+ r[expr.xreplace({x: exp(x)})] = var
477
+ for var, expr in s.rewrites.items():
478
+ r.rewrites[var] = s.rewrites[var].xreplace({x: exp(x)})
479
+ return r
480
+
481
+
482
+ def moveup(l, x):
483
+ return [e.xreplace({x: exp(x)}) for e in l]
484
+
485
+
486
+ @debug
487
+ @timeit
488
+ def calculate_series(e, x, logx=None):
489
+ """ Calculates at least one term of the series of ``e`` in ``x``.
490
+
491
+ This is a place that fails most often, so it is in its own function.
492
+ """
493
+
494
+ SymPyDeprecationWarning(
495
+ feature="calculate_series",
496
+ useinstead="series() with suitable n, or as_leading_term",
497
+ issue=21838,
498
+ deprecated_since_version="1.12"
499
+ ).warn()
500
+
501
+ from sympy.simplify.powsimp import powdenest
502
+
503
+ for t in e.lseries(x, logx=logx):
504
+ # bottom_up function is required for a specific case - when e is
505
+ # -exp(p/(p + 1)) + exp(-p**2/(p + 1) + p)
506
+ t = bottom_up(t, lambda w:
507
+ getattr(w, 'normal', lambda: w)())
508
+ # And the expression
509
+ # `(-sin(1/x) + sin((x + exp(x))*exp(-x)/x))*exp(x)`
510
+ # from the first test of test_gruntz_eval_special needs to
511
+ # be expanded. But other forms need to be have at least
512
+ # factor_terms applied. `factor` accomplishes both and is
513
+ # faster than using `factor_terms` for the gruntz suite. It
514
+ # does not appear that use of `cancel` is necessary.
515
+ # t = cancel(t, expand=False)
516
+ t = t.factor()
517
+
518
+ if t.has(exp) and t.has(log):
519
+ t = powdenest(t)
520
+
521
+ if not t.is_zero:
522
+ break
523
+
524
+ return t
525
+
526
+
527
+ @debug
528
+ @timeit
529
+ @cacheit
530
+ def mrv_leadterm(e, x):
531
+ """Returns (c0, e0) for e."""
532
+ Omega = SubsSet()
533
+ if not e.has(x):
534
+ return (e, S.Zero)
535
+ if Omega == SubsSet():
536
+ Omega, exps = mrv(e, x)
537
+ if not Omega:
538
+ # e really does not depend on x after simplification
539
+ return exps, S.Zero
540
+ if x in Omega:
541
+ # move the whole omega up (exponentiate each term):
542
+ Omega_up = moveup2(Omega, x)
543
+ exps_up = moveup([exps], x)[0]
544
+ # NOTE: there is no need to move this down!
545
+ Omega = Omega_up
546
+ exps = exps_up
547
+ #
548
+ # The positive dummy, w, is used here so log(w*2) etc. will expand;
549
+ # a unique dummy is needed in this algorithm
550
+ #
551
+ # For limits of complex functions, the algorithm would have to be
552
+ # improved, or just find limits of Re and Im components separately.
553
+ #
554
+ w = Dummy("w", positive=True)
555
+ f, logw = rewrite(exps, Omega, x, w)
556
+ try:
557
+ lt = f.leadterm(w, logx=logw)
558
+ except (NotImplementedError, PoleError, ValueError):
559
+ n0 = 1
560
+ _series = Order(1)
561
+ incr = S.One
562
+ while _series.is_Order:
563
+ _series = f._eval_nseries(w, n=n0+incr, logx=logw)
564
+ incr *= 2
565
+ series = _series.expand().removeO()
566
+ try:
567
+ lt = series.leadterm(w, logx=logw)
568
+ except (NotImplementedError, PoleError, ValueError):
569
+ lt = f.as_coeff_exponent(w)
570
+ if lt[0].has(w):
571
+ base = f.as_base_exp()[0].as_coeff_exponent(w)
572
+ ex = f.as_base_exp()[1]
573
+ lt = (base[0]**ex, base[1]*ex)
574
+ return (lt[0].subs(log(w), logw), lt[1])
575
+
576
+
577
+ def build_expression_tree(Omega, rewrites):
578
+ r""" Helper function for rewrite.
579
+
580
+ We need to sort Omega (mrv set) so that we replace an expression before
581
+ we replace any expression in terms of which it has to be rewritten::
582
+
583
+ e1 ---> e2 ---> e3
584
+ \
585
+ -> e4
586
+
587
+ Here we can do e1, e2, e3, e4 or e1, e2, e4, e3.
588
+ To do this we assemble the nodes into a tree, and sort them by height.
589
+
590
+ This function builds the tree, rewrites then sorts the nodes.
591
+ """
592
+ class Node:
593
+ def __init__(self):
594
+ self.before = []
595
+ self.expr = None
596
+ self.var = None
597
+ def ht(self):
598
+ return reduce(lambda x, y: x + y,
599
+ [x.ht() for x in self.before], 1)
600
+ nodes = {}
601
+ for expr, v in Omega:
602
+ n = Node()
603
+ n.var = v
604
+ n.expr = expr
605
+ nodes[v] = n
606
+ for _, v in Omega:
607
+ if v in rewrites:
608
+ n = nodes[v]
609
+ r = rewrites[v]
610
+ for _, v2 in Omega:
611
+ if r.has(v2):
612
+ n.before.append(nodes[v2])
613
+
614
+ return nodes
615
+
616
+
617
+ @debug
618
+ @timeit
619
+ def rewrite(e, Omega, x, wsym):
620
+ """e(x) ... the function
621
+ Omega ... the mrv set
622
+ wsym ... the symbol which is going to be used for w
623
+
624
+ Returns the rewritten e in terms of w and log(w). See test_rewrite1()
625
+ for examples and correct results.
626
+ """
627
+
628
+ from sympy import AccumBounds
629
+ if not isinstance(Omega, SubsSet):
630
+ raise TypeError("Omega should be an instance of SubsSet")
631
+ if len(Omega) == 0:
632
+ raise ValueError("Length cannot be 0")
633
+ # all items in Omega must be exponentials
634
+ for t in Omega.keys():
635
+ if not isinstance(t, exp):
636
+ raise ValueError("Value should be exp")
637
+ rewrites = Omega.rewrites
638
+ Omega = list(Omega.items())
639
+
640
+ nodes = build_expression_tree(Omega, rewrites)
641
+ Omega.sort(key=lambda x: nodes[x[1]].ht(), reverse=True)
642
+
643
+ # make sure we know the sign of each exp() term; after the loop,
644
+ # g is going to be the "w" - the simplest one in the mrv set
645
+ for g, _ in Omega:
646
+ sig = sign(g.exp, x)
647
+ if sig != 1 and sig != -1 and not sig.has(AccumBounds):
648
+ raise NotImplementedError('Result depends on the sign of %s' % sig)
649
+ if sig == 1:
650
+ wsym = 1/wsym # if g goes to oo, substitute 1/w
651
+ # O2 is a list, which results by rewriting each item in Omega using "w"
652
+ O2 = []
653
+ denominators = []
654
+ for f, var in Omega:
655
+ c = limitinf(f.exp/g.exp, x)
656
+ if c.is_Rational:
657
+ denominators.append(c.q)
658
+ arg = f.exp
659
+ if var in rewrites:
660
+ if not isinstance(rewrites[var], exp):
661
+ raise ValueError("Value should be exp")
662
+ arg = rewrites[var].args[0]
663
+ O2.append((var, exp((arg - c*g.exp).expand())*wsym**c))
664
+
665
+ # Remember that Omega contains subexpressions of "e". So now we find
666
+ # them in "e" and substitute them for our rewriting, stored in O2
667
+
668
+ # the following powsimp is necessary to automatically combine exponentials,
669
+ # so that the .xreplace() below succeeds:
670
+ # TODO this should not be necessary
671
+ from sympy.simplify.powsimp import powsimp
672
+ f = powsimp(e, deep=True, combine='exp')
673
+ for a, b in O2:
674
+ f = f.xreplace({a: b})
675
+
676
+ for _, var in Omega:
677
+ assert not f.has(var)
678
+
679
+ # finally compute the logarithm of w (logw).
680
+ logw = g.exp
681
+ if sig == 1:
682
+ logw = -logw # log(w)->log(1/w)=-log(w)
683
+
684
+ # Some parts of SymPy have difficulty computing series expansions with
685
+ # non-integral exponents. The following heuristic improves the situation:
686
+ exponent = reduce(ilcm, denominators, 1)
687
+ f = f.subs({wsym: wsym**exponent})
688
+ logw /= exponent
689
+
690
+ # bottom_up function is required for a specific case - when f is
691
+ # -exp(p/(p + 1)) + exp(-p**2/(p + 1) + p). No current simplification
692
+ # methods reduce this to 0 while not expanding polynomials.
693
+ f = bottom_up(f, lambda w: getattr(w, 'normal', lambda: w)())
694
+ f = expand_mul(f)
695
+
696
+ return f, logw
697
+
698
+
699
+ def gruntz(e, z, z0, dir="+"):
700
+ """
701
+ Compute the limit of e(z) at the point z0 using the Gruntz algorithm.
702
+
703
+ Explanation
704
+ ===========
705
+
706
+ ``z0`` can be any expression, including oo and -oo.
707
+
708
+ For ``dir="+"`` (default) it calculates the limit from the right
709
+ (z->z0+) and for ``dir="-"`` the limit from the left (z->z0-). For infinite z0
710
+ (oo or -oo), the dir argument does not matter.
711
+
712
+ This algorithm is fully described in the module docstring in the gruntz.py
713
+ file. It relies heavily on the series expansion. Most frequently, gruntz()
714
+ is only used if the faster limit() function (which uses heuristics) fails.
715
+ """
716
+ if not z.is_symbol:
717
+ raise NotImplementedError("Second argument must be a Symbol")
718
+
719
+ # convert all limits to the limit z->oo; sign of z is handled in limitinf
720
+ r = None
721
+ if z0 in (oo, I*oo):
722
+ e0 = e
723
+ elif z0 in (-oo, -I*oo):
724
+ e0 = e.subs(z, -z)
725
+ else:
726
+ if str(dir) == "-":
727
+ e0 = e.subs(z, z0 - 1/z)
728
+ elif str(dir) == "+":
729
+ e0 = e.subs(z, z0 + 1/z)
730
+ else:
731
+ raise NotImplementedError("dir must be '+' or '-'")
732
+
733
+ r = limitinf(e0, z)
734
+
735
+ # This is a bit of a heuristic for nice results... we always rewrite
736
+ # tractable functions in terms of familiar intractable ones.
737
+ # It might be nicer to rewrite the exactly to what they were initially,
738
+ # but that would take some work to implement.
739
+ return r.rewrite('intractable', deep=True)
evalkit_internvl/lib/python3.10/site-packages/sympy/series/kauers.py ADDED
@@ -0,0 +1,51 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ def finite_diff(expression, variable, increment=1):
2
+ """
3
+ Takes as input a polynomial expression and the variable used to construct
4
+ it and returns the difference between function's value when the input is
5
+ incremented to 1 and the original function value. If you want an increment
6
+ other than one supply it as a third argument.
7
+
8
+ Examples
9
+ ========
10
+
11
+ >>> from sympy.abc import x, y, z
12
+ >>> from sympy.series.kauers import finite_diff
13
+ >>> finite_diff(x**2, x)
14
+ 2*x + 1
15
+ >>> finite_diff(y**3 + 2*y**2 + 3*y + 4, y)
16
+ 3*y**2 + 7*y + 6
17
+ >>> finite_diff(x**2 + 3*x + 8, x, 2)
18
+ 4*x + 10
19
+ >>> finite_diff(z**3 + 8*z, z, 3)
20
+ 9*z**2 + 27*z + 51
21
+ """
22
+ expression = expression.expand()
23
+ expression2 = expression.subs(variable, variable + increment)
24
+ expression2 = expression2.expand()
25
+ return expression2 - expression
26
+
27
+ def finite_diff_kauers(sum):
28
+ """
29
+ Takes as input a Sum instance and returns the difference between the sum
30
+ with the upper index incremented by 1 and the original sum. For example,
31
+ if S(n) is a sum, then finite_diff_kauers will return S(n + 1) - S(n).
32
+
33
+ Examples
34
+ ========
35
+
36
+ >>> from sympy.series.kauers import finite_diff_kauers
37
+ >>> from sympy import Sum
38
+ >>> from sympy.abc import x, y, m, n, k
39
+ >>> finite_diff_kauers(Sum(k, (k, 1, n)))
40
+ n + 1
41
+ >>> finite_diff_kauers(Sum(1/k, (k, 1, n)))
42
+ 1/(n + 1)
43
+ >>> finite_diff_kauers(Sum((x*y**2), (x, 1, n), (y, 1, m)))
44
+ (m + 1)**2*(n + 1)
45
+ >>> finite_diff_kauers(Sum((x*y), (x, 1, m), (y, 1, n)))
46
+ (m + 1)*(n + 1)
47
+ """
48
+ function = sum.function
49
+ for l in sum.limits:
50
+ function = function.subs(l[0], l[- 1] + 1)
51
+ return function
evalkit_internvl/lib/python3.10/site-packages/sympy/series/limits.py ADDED
@@ -0,0 +1,385 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ from sympy.calculus.accumulationbounds import AccumBounds
2
+ from sympy.core import S, Symbol, Add, sympify, Expr, PoleError, Mul
3
+ from sympy.core.exprtools import factor_terms
4
+ from sympy.core.numbers import Float, _illegal
5
+ from sympy.functions.combinatorial.factorials import factorial
6
+ from sympy.functions.elementary.complexes import (Abs, sign, arg, re)
7
+ from sympy.functions.elementary.exponential import (exp, log)
8
+ from sympy.functions.special.gamma_functions import gamma
9
+ from sympy.polys import PolynomialError, factor
10
+ from sympy.series.order import Order
11
+ from .gruntz import gruntz
12
+
13
+ def limit(e, z, z0, dir="+"):
14
+ """Computes the limit of ``e(z)`` at the point ``z0``.
15
+
16
+ Parameters
17
+ ==========
18
+
19
+ e : expression, the limit of which is to be taken
20
+
21
+ z : symbol representing the variable in the limit.
22
+ Other symbols are treated as constants. Multivariate limits
23
+ are not supported.
24
+
25
+ z0 : the value toward which ``z`` tends. Can be any expression,
26
+ including ``oo`` and ``-oo``.
27
+
28
+ dir : string, optional (default: "+")
29
+ The limit is bi-directional if ``dir="+-"``, from the right
30
+ (z->z0+) if ``dir="+"``, and from the left (z->z0-) if
31
+ ``dir="-"``. For infinite ``z0`` (``oo`` or ``-oo``), the ``dir``
32
+ argument is determined from the direction of the infinity
33
+ (i.e., ``dir="-"`` for ``oo``).
34
+
35
+ Examples
36
+ ========
37
+
38
+ >>> from sympy import limit, sin, oo
39
+ >>> from sympy.abc import x
40
+ >>> limit(sin(x)/x, x, 0)
41
+ 1
42
+ >>> limit(1/x, x, 0) # default dir='+'
43
+ oo
44
+ >>> limit(1/x, x, 0, dir="-")
45
+ -oo
46
+ >>> limit(1/x, x, 0, dir='+-')
47
+ zoo
48
+ >>> limit(1/x, x, oo)
49
+ 0
50
+
51
+ Notes
52
+ =====
53
+
54
+ First we try some heuristics for easy and frequent cases like "x", "1/x",
55
+ "x**2" and similar, so that it's fast. For all other cases, we use the
56
+ Gruntz algorithm (see the gruntz() function).
57
+
58
+ See Also
59
+ ========
60
+
61
+ limit_seq : returns the limit of a sequence.
62
+ """
63
+
64
+ return Limit(e, z, z0, dir).doit(deep=False)
65
+
66
+
67
+ def heuristics(e, z, z0, dir):
68
+ """Computes the limit of an expression term-wise.
69
+ Parameters are the same as for the ``limit`` function.
70
+ Works with the arguments of expression ``e`` one by one, computing
71
+ the limit of each and then combining the results. This approach
72
+ works only for simple limits, but it is fast.
73
+ """
74
+
75
+ rv = None
76
+ if z0 is S.Infinity:
77
+ rv = limit(e.subs(z, 1/z), z, S.Zero, "+")
78
+ if isinstance(rv, Limit):
79
+ return
80
+ elif e.is_Mul or e.is_Add or e.is_Pow or e.is_Function:
81
+ r = []
82
+ from sympy.simplify.simplify import together
83
+ for a in e.args:
84
+ l = limit(a, z, z0, dir)
85
+ if l.has(S.Infinity) and l.is_finite is None:
86
+ if isinstance(e, Add):
87
+ m = factor_terms(e)
88
+ if not isinstance(m, Mul): # try together
89
+ m = together(m)
90
+ if not isinstance(m, Mul): # try factor if the previous methods failed
91
+ m = factor(e)
92
+ if isinstance(m, Mul):
93
+ return heuristics(m, z, z0, dir)
94
+ return
95
+ return
96
+ elif isinstance(l, Limit):
97
+ return
98
+ elif l is S.NaN:
99
+ return
100
+ else:
101
+ r.append(l)
102
+ if r:
103
+ rv = e.func(*r)
104
+ if rv is S.NaN and e.is_Mul and any(isinstance(rr, AccumBounds) for rr in r):
105
+ r2 = []
106
+ e2 = []
107
+ for ii, rval in enumerate(r):
108
+ if isinstance(rval, AccumBounds):
109
+ r2.append(rval)
110
+ else:
111
+ e2.append(e.args[ii])
112
+
113
+ if len(e2) > 0:
114
+ e3 = Mul(*e2).simplify()
115
+ l = limit(e3, z, z0, dir)
116
+ rv = l * Mul(*r2)
117
+
118
+ if rv is S.NaN:
119
+ try:
120
+ from sympy.simplify.ratsimp import ratsimp
121
+ rat_e = ratsimp(e)
122
+ except PolynomialError:
123
+ return
124
+ if rat_e is S.NaN or rat_e == e:
125
+ return
126
+ return limit(rat_e, z, z0, dir)
127
+ return rv
128
+
129
+
130
+ class Limit(Expr):
131
+ """Represents an unevaluated limit.
132
+
133
+ Examples
134
+ ========
135
+
136
+ >>> from sympy import Limit, sin
137
+ >>> from sympy.abc import x
138
+ >>> Limit(sin(x)/x, x, 0)
139
+ Limit(sin(x)/x, x, 0, dir='+')
140
+ >>> Limit(1/x, x, 0, dir="-")
141
+ Limit(1/x, x, 0, dir='-')
142
+
143
+ """
144
+
145
+ def __new__(cls, e, z, z0, dir="+"):
146
+ e = sympify(e)
147
+ z = sympify(z)
148
+ z0 = sympify(z0)
149
+
150
+ if z0 in (S.Infinity, S.ImaginaryUnit*S.Infinity):
151
+ dir = "-"
152
+ elif z0 in (S.NegativeInfinity, S.ImaginaryUnit*S.NegativeInfinity):
153
+ dir = "+"
154
+
155
+ if(z0.has(z)):
156
+ raise NotImplementedError("Limits approaching a variable point are"
157
+ " not supported (%s -> %s)" % (z, z0))
158
+ if isinstance(dir, str):
159
+ dir = Symbol(dir)
160
+ elif not isinstance(dir, Symbol):
161
+ raise TypeError("direction must be of type basestring or "
162
+ "Symbol, not %s" % type(dir))
163
+ if str(dir) not in ('+', '-', '+-'):
164
+ raise ValueError("direction must be one of '+', '-' "
165
+ "or '+-', not %s" % dir)
166
+
167
+ obj = Expr.__new__(cls)
168
+ obj._args = (e, z, z0, dir)
169
+ return obj
170
+
171
+
172
+ @property
173
+ def free_symbols(self):
174
+ e = self.args[0]
175
+ isyms = e.free_symbols
176
+ isyms.difference_update(self.args[1].free_symbols)
177
+ isyms.update(self.args[2].free_symbols)
178
+ return isyms
179
+
180
+
181
+ def pow_heuristics(self, e):
182
+ _, z, z0, _ = self.args
183
+ b1, e1 = e.base, e.exp
184
+ if not b1.has(z):
185
+ res = limit(e1*log(b1), z, z0)
186
+ return exp(res)
187
+
188
+ ex_lim = limit(e1, z, z0)
189
+ base_lim = limit(b1, z, z0)
190
+
191
+ if base_lim is S.One:
192
+ if ex_lim in (S.Infinity, S.NegativeInfinity):
193
+ res = limit(e1*(b1 - 1), z, z0)
194
+ return exp(res)
195
+ if base_lim is S.NegativeInfinity and ex_lim is S.Infinity:
196
+ return S.ComplexInfinity
197
+
198
+
199
+ def doit(self, **hints):
200
+ """Evaluates the limit.
201
+
202
+ Parameters
203
+ ==========
204
+
205
+ deep : bool, optional (default: True)
206
+ Invoke the ``doit`` method of the expressions involved before
207
+ taking the limit.
208
+
209
+ hints : optional keyword arguments
210
+ To be passed to ``doit`` methods; only used if deep is True.
211
+ """
212
+
213
+ e, z, z0, dir = self.args
214
+
215
+ if str(dir) == '+-':
216
+ r = limit(e, z, z0, dir='+')
217
+ l = limit(e, z, z0, dir='-')
218
+ if isinstance(r, Limit) and isinstance(l, Limit):
219
+ if r.args[0] == l.args[0]:
220
+ return self
221
+ if r == l:
222
+ return l
223
+ if r.is_infinite and l.is_infinite:
224
+ return S.ComplexInfinity
225
+ raise ValueError("The limit does not exist since "
226
+ "left hand limit = %s and right hand limit = %s"
227
+ % (l, r))
228
+
229
+ if z0 is S.ComplexInfinity:
230
+ raise NotImplementedError("Limits at complex "
231
+ "infinity are not implemented")
232
+
233
+ if z0.is_infinite:
234
+ cdir = sign(z0)
235
+ cdir = cdir/abs(cdir)
236
+ e = e.subs(z, cdir*z)
237
+ dir = "-"
238
+ z0 = S.Infinity
239
+
240
+ if hints.get('deep', True):
241
+ e = e.doit(**hints)
242
+ z = z.doit(**hints)
243
+ z0 = z0.doit(**hints)
244
+
245
+ if e == z:
246
+ return z0
247
+
248
+ if not e.has(z):
249
+ return e
250
+
251
+ if z0 is S.NaN:
252
+ return S.NaN
253
+
254
+ if e.has(*_illegal):
255
+ return self
256
+
257
+ if e.is_Order:
258
+ return Order(limit(e.expr, z, z0), *e.args[1:])
259
+
260
+ cdir = 0
261
+ if str(dir) == "+":
262
+ cdir = 1
263
+ elif str(dir) == "-":
264
+ cdir = -1
265
+
266
+ def set_signs(expr):
267
+ if not expr.args:
268
+ return expr
269
+ newargs = tuple(set_signs(arg) for arg in expr.args)
270
+ if newargs != expr.args:
271
+ expr = expr.func(*newargs)
272
+ abs_flag = isinstance(expr, Abs)
273
+ arg_flag = isinstance(expr, arg)
274
+ sign_flag = isinstance(expr, sign)
275
+ if abs_flag or sign_flag or arg_flag:
276
+ sig = limit(expr.args[0], z, z0, dir)
277
+ if sig.is_zero:
278
+ sig = limit(1/expr.args[0], z, z0, dir)
279
+ if sig.is_extended_real:
280
+ if (sig < 0) == True:
281
+ return (-expr.args[0] if abs_flag else
282
+ S.NegativeOne if sign_flag else S.Pi)
283
+ elif (sig > 0) == True:
284
+ return (expr.args[0] if abs_flag else
285
+ S.One if sign_flag else S.Zero)
286
+ return expr
287
+
288
+ if e.has(Float):
289
+ # Convert floats like 0.5 to exact SymPy numbers like S.Half, to
290
+ # prevent rounding errors which can lead to unexpected execution
291
+ # of conditional blocks that work on comparisons
292
+ # Also see comments in https://github.com/sympy/sympy/issues/19453
293
+ from sympy.simplify.simplify import nsimplify
294
+ e = nsimplify(e)
295
+ e = set_signs(e)
296
+
297
+
298
+ if e.is_meromorphic(z, z0):
299
+ if z0 is S.Infinity:
300
+ newe = e.subs(z, 1/z)
301
+ # cdir changes sign as oo- should become 0+
302
+ cdir = -cdir
303
+ else:
304
+ newe = e.subs(z, z + z0)
305
+ try:
306
+ coeff, ex = newe.leadterm(z, cdir=cdir)
307
+ except ValueError:
308
+ pass
309
+ else:
310
+ if ex > 0:
311
+ return S.Zero
312
+ elif ex == 0:
313
+ return coeff
314
+ if cdir == 1 or not(int(ex) & 1):
315
+ return S.Infinity*sign(coeff)
316
+ elif cdir == -1:
317
+ return S.NegativeInfinity*sign(coeff)
318
+ else:
319
+ return S.ComplexInfinity
320
+
321
+ if z0 is S.Infinity:
322
+ if e.is_Mul:
323
+ e = factor_terms(e)
324
+ newe = e.subs(z, 1/z)
325
+ # cdir changes sign as oo- should become 0+
326
+ cdir = -cdir
327
+ else:
328
+ newe = e.subs(z, z + z0)
329
+ try:
330
+ coeff, ex = newe.leadterm(z, cdir=cdir)
331
+ except (ValueError, NotImplementedError, PoleError):
332
+ # The NotImplementedError catching is for custom functions
333
+ from sympy.simplify.powsimp import powsimp
334
+ e = powsimp(e)
335
+ if e.is_Pow:
336
+ r = self.pow_heuristics(e)
337
+ if r is not None:
338
+ return r
339
+ try:
340
+ coeff = newe.as_leading_term(z, cdir=cdir)
341
+ if coeff != newe and (coeff.has(exp) or coeff.has(S.Exp1)):
342
+ return gruntz(coeff, z, 0, "-" if re(cdir).is_negative else "+")
343
+ except (ValueError, NotImplementedError, PoleError):
344
+ pass
345
+ else:
346
+ if isinstance(coeff, AccumBounds) and ex == S.Zero:
347
+ return coeff
348
+ if coeff.has(S.Infinity, S.NegativeInfinity, S.ComplexInfinity, S.NaN):
349
+ return self
350
+ if not coeff.has(z):
351
+ if ex.is_positive:
352
+ return S.Zero
353
+ elif ex == 0:
354
+ return coeff
355
+ elif ex.is_negative:
356
+ if cdir == 1:
357
+ return S.Infinity*sign(coeff)
358
+ elif cdir == -1:
359
+ return S.NegativeInfinity*sign(coeff)*S.NegativeOne**(S.One + ex)
360
+ else:
361
+ return S.ComplexInfinity
362
+ else:
363
+ raise NotImplementedError("Not sure of sign of %s" % ex)
364
+
365
+ # gruntz fails on factorials but works with the gamma function
366
+ # If no factorial term is present, e should remain unchanged.
367
+ # factorial is defined to be zero for negative inputs (which
368
+ # differs from gamma) so only rewrite for positive z0.
369
+ if z0.is_extended_positive:
370
+ e = e.rewrite(factorial, gamma)
371
+
372
+ l = None
373
+
374
+ try:
375
+ r = gruntz(e, z, z0, dir)
376
+ if r is S.NaN or l is S.NaN:
377
+ raise PoleError()
378
+ except (PoleError, ValueError):
379
+ if l is not None:
380
+ raise
381
+ r = heuristics(e, z, z0, dir)
382
+ if r is None:
383
+ return self
384
+
385
+ return r
evalkit_internvl/lib/python3.10/site-packages/sympy/series/limitseq.py ADDED
@@ -0,0 +1,257 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """Limits of sequences"""
2
+
3
+ from sympy.calculus.accumulationbounds import AccumulationBounds
4
+ from sympy.core.add import Add
5
+ from sympy.core.function import PoleError
6
+ from sympy.core.power import Pow
7
+ from sympy.core.singleton import S
8
+ from sympy.core.symbol import Dummy
9
+ from sympy.core.sympify import sympify
10
+ from sympy.functions.combinatorial.numbers import fibonacci
11
+ from sympy.functions.combinatorial.factorials import factorial, subfactorial
12
+ from sympy.functions.special.gamma_functions import gamma
13
+ from sympy.functions.elementary.complexes import Abs
14
+ from sympy.functions.elementary.miscellaneous import Max, Min
15
+ from sympy.functions.elementary.trigonometric import cos, sin
16
+ from sympy.series.limits import Limit
17
+
18
+
19
+ def difference_delta(expr, n=None, step=1):
20
+ """Difference Operator.
21
+
22
+ Explanation
23
+ ===========
24
+
25
+ Discrete analog of differential operator. Given a sequence x[n],
26
+ returns the sequence x[n + step] - x[n].
27
+
28
+ Examples
29
+ ========
30
+
31
+ >>> from sympy import difference_delta as dd
32
+ >>> from sympy.abc import n
33
+ >>> dd(n*(n + 1), n)
34
+ 2*n + 2
35
+ >>> dd(n*(n + 1), n, 2)
36
+ 4*n + 6
37
+
38
+ References
39
+ ==========
40
+
41
+ .. [1] https://reference.wolfram.com/language/ref/DifferenceDelta.html
42
+ """
43
+ expr = sympify(expr)
44
+
45
+ if n is None:
46
+ f = expr.free_symbols
47
+ if len(f) == 1:
48
+ n = f.pop()
49
+ elif len(f) == 0:
50
+ return S.Zero
51
+ else:
52
+ raise ValueError("Since there is more than one variable in the"
53
+ " expression, a variable must be supplied to"
54
+ " take the difference of %s" % expr)
55
+ step = sympify(step)
56
+ if step.is_number is False or step.is_finite is False:
57
+ raise ValueError("Step should be a finite number.")
58
+
59
+ if hasattr(expr, '_eval_difference_delta'):
60
+ result = expr._eval_difference_delta(n, step)
61
+ if result:
62
+ return result
63
+
64
+ return expr.subs(n, n + step) - expr
65
+
66
+
67
+ def dominant(expr, n):
68
+ """Finds the dominant term in a sum, that is a term that dominates
69
+ every other term.
70
+
71
+ Explanation
72
+ ===========
73
+
74
+ If limit(a/b, n, oo) is oo then a dominates b.
75
+ If limit(a/b, n, oo) is 0 then b dominates a.
76
+ Otherwise, a and b are comparable.
77
+
78
+ If there is no unique dominant term, then returns ``None``.
79
+
80
+ Examples
81
+ ========
82
+
83
+ >>> from sympy import Sum
84
+ >>> from sympy.series.limitseq import dominant
85
+ >>> from sympy.abc import n, k
86
+ >>> dominant(5*n**3 + 4*n**2 + n + 1, n)
87
+ 5*n**3
88
+ >>> dominant(2**n + Sum(k, (k, 0, n)), n)
89
+ 2**n
90
+
91
+ See Also
92
+ ========
93
+
94
+ sympy.series.limitseq.dominant
95
+ """
96
+ terms = Add.make_args(expr.expand(func=True))
97
+ term0 = terms[-1]
98
+ comp = [term0] # comparable terms
99
+ for t in terms[:-1]:
100
+ r = term0/t
101
+ e = r.gammasimp()
102
+ if e == r:
103
+ e = r.factor()
104
+ l = limit_seq(e, n)
105
+ if l is None:
106
+ return None
107
+ elif l.is_zero:
108
+ term0 = t
109
+ comp = [term0]
110
+ elif l not in [S.Infinity, S.NegativeInfinity]:
111
+ comp.append(t)
112
+ if len(comp) > 1:
113
+ return None
114
+ return term0
115
+
116
+
117
+ def _limit_inf(expr, n):
118
+ try:
119
+ return Limit(expr, n, S.Infinity).doit(deep=False)
120
+ except (NotImplementedError, PoleError):
121
+ return None
122
+
123
+
124
+ def _limit_seq(expr, n, trials):
125
+ from sympy.concrete.summations import Sum
126
+
127
+ for i in range(trials):
128
+ if not expr.has(Sum):
129
+ result = _limit_inf(expr, n)
130
+ if result is not None:
131
+ return result
132
+
133
+ num, den = expr.as_numer_denom()
134
+ if not den.has(n) or not num.has(n):
135
+ result = _limit_inf(expr.doit(), n)
136
+ if result is not None:
137
+ return result
138
+ return None
139
+
140
+ num, den = (difference_delta(t.expand(), n) for t in [num, den])
141
+ expr = (num / den).gammasimp()
142
+
143
+ if not expr.has(Sum):
144
+ result = _limit_inf(expr, n)
145
+ if result is not None:
146
+ return result
147
+
148
+ num, den = expr.as_numer_denom()
149
+
150
+ num = dominant(num, n)
151
+ if num is None:
152
+ return None
153
+
154
+ den = dominant(den, n)
155
+ if den is None:
156
+ return None
157
+
158
+ expr = (num / den).gammasimp()
159
+
160
+
161
+ def limit_seq(expr, n=None, trials=5):
162
+ """Finds the limit of a sequence as index ``n`` tends to infinity.
163
+
164
+ Parameters
165
+ ==========
166
+
167
+ expr : Expr
168
+ SymPy expression for the ``n-th`` term of the sequence
169
+ n : Symbol, optional
170
+ The index of the sequence, an integer that tends to positive
171
+ infinity. If None, inferred from the expression unless it has
172
+ multiple symbols.
173
+ trials: int, optional
174
+ The algorithm is highly recursive. ``trials`` is a safeguard from
175
+ infinite recursion in case the limit is not easily computed by the
176
+ algorithm. Try increasing ``trials`` if the algorithm returns ``None``.
177
+
178
+ Admissible Terms
179
+ ================
180
+
181
+ The algorithm is designed for sequences built from rational functions,
182
+ indefinite sums, and indefinite products over an indeterminate n. Terms of
183
+ alternating sign are also allowed, but more complex oscillatory behavior is
184
+ not supported.
185
+
186
+ Examples
187
+ ========
188
+
189
+ >>> from sympy import limit_seq, Sum, binomial
190
+ >>> from sympy.abc import n, k, m
191
+ >>> limit_seq((5*n**3 + 3*n**2 + 4) / (3*n**3 + 4*n - 5), n)
192
+ 5/3
193
+ >>> limit_seq(binomial(2*n, n) / Sum(binomial(2*k, k), (k, 1, n)), n)
194
+ 3/4
195
+ >>> limit_seq(Sum(k**2 * Sum(2**m/m, (m, 1, k)), (k, 1, n)) / (2**n*n), n)
196
+ 4
197
+
198
+ See Also
199
+ ========
200
+
201
+ sympy.series.limitseq.dominant
202
+
203
+ References
204
+ ==========
205
+
206
+ .. [1] Computing Limits of Sequences - Manuel Kauers
207
+ """
208
+
209
+ from sympy.concrete.summations import Sum
210
+ if n is None:
211
+ free = expr.free_symbols
212
+ if len(free) == 1:
213
+ n = free.pop()
214
+ elif not free:
215
+ return expr
216
+ else:
217
+ raise ValueError("Expression has more than one variable. "
218
+ "Please specify a variable.")
219
+ elif n not in expr.free_symbols:
220
+ return expr
221
+
222
+ expr = expr.rewrite(fibonacci, S.GoldenRatio)
223
+ expr = expr.rewrite(factorial, subfactorial, gamma)
224
+ n_ = Dummy("n", integer=True, positive=True)
225
+ n1 = Dummy("n", odd=True, positive=True)
226
+ n2 = Dummy("n", even=True, positive=True)
227
+
228
+ # If there is a negative term raised to a power involving n, or a
229
+ # trigonometric function, then consider even and odd n separately.
230
+ powers = (p.as_base_exp() for p in expr.atoms(Pow))
231
+ if (any(b.is_negative and e.has(n) for b, e in powers) or
232
+ expr.has(cos, sin)):
233
+ L1 = _limit_seq(expr.xreplace({n: n1}), n1, trials)
234
+ if L1 is not None:
235
+ L2 = _limit_seq(expr.xreplace({n: n2}), n2, trials)
236
+ if L1 != L2:
237
+ if L1.is_comparable and L2.is_comparable:
238
+ return AccumulationBounds(Min(L1, L2), Max(L1, L2))
239
+ else:
240
+ return None
241
+ else:
242
+ L1 = _limit_seq(expr.xreplace({n: n_}), n_, trials)
243
+ if L1 is not None:
244
+ return L1
245
+ else:
246
+ if expr.is_Add:
247
+ limits = [limit_seq(term, n, trials) for term in expr.args]
248
+ if any(result is None for result in limits):
249
+ return None
250
+ else:
251
+ return Add(*limits)
252
+ # Maybe the absolute value is easier to deal with (though not if
253
+ # it has a Sum). If it tends to 0, the limit is 0.
254
+ elif not expr.has(Sum):
255
+ lim = _limit_seq(Abs(expr.xreplace({n: n_})), n_, trials)
256
+ if lim is not None and lim.is_zero:
257
+ return S.Zero
evalkit_internvl/lib/python3.10/site-packages/sympy/series/order.py ADDED
@@ -0,0 +1,517 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ from sympy.core import S, sympify, Expr, Dummy, Add, Mul
2
+ from sympy.core.cache import cacheit
3
+ from sympy.core.containers import Tuple
4
+ from sympy.core.function import Function, PoleError, expand_power_base, expand_log
5
+ from sympy.core.sorting import default_sort_key
6
+ from sympy.functions.elementary.exponential import exp, log
7
+ from sympy.sets.sets import Complement
8
+ from sympy.utilities.iterables import uniq, is_sequence
9
+
10
+
11
+ class Order(Expr):
12
+ r""" Represents the limiting behavior of some function.
13
+
14
+ Explanation
15
+ ===========
16
+
17
+ The order of a function characterizes the function based on the limiting
18
+ behavior of the function as it goes to some limit. Only taking the limit
19
+ point to be a number is currently supported. This is expressed in
20
+ big O notation [1]_.
21
+
22
+ The formal definition for the order of a function `g(x)` about a point `a`
23
+ is such that `g(x) = O(f(x))` as `x \rightarrow a` if and only if there
24
+ exists a `\delta > 0` and an `M > 0` such that `|g(x)| \leq M|f(x)|` for
25
+ `|x-a| < \delta`. This is equivalent to `\limsup_{x \rightarrow a}
26
+ |g(x)/f(x)| < \infty`.
27
+
28
+ Let's illustrate it on the following example by taking the expansion of
29
+ `\sin(x)` about 0:
30
+
31
+ .. math ::
32
+ \sin(x) = x - x^3/3! + O(x^5)
33
+
34
+ where in this case `O(x^5) = x^5/5! - x^7/7! + \cdots`. By the definition
35
+ of `O`, there is a `\delta > 0` and an `M` such that:
36
+
37
+ .. math ::
38
+ |x^5/5! - x^7/7! + ....| <= M|x^5| \text{ for } |x| < \delta
39
+
40
+ or by the alternate definition:
41
+
42
+ .. math ::
43
+ \lim_{x \rightarrow 0} | (x^5/5! - x^7/7! + ....) / x^5| < \infty
44
+
45
+ which surely is true, because
46
+
47
+ .. math ::
48
+ \lim_{x \rightarrow 0} | (x^5/5! - x^7/7! + ....) / x^5| = 1/5!
49
+
50
+
51
+ As it is usually used, the order of a function can be intuitively thought
52
+ of representing all terms of powers greater than the one specified. For
53
+ example, `O(x^3)` corresponds to any terms proportional to `x^3,
54
+ x^4,\ldots` and any higher power. For a polynomial, this leaves terms
55
+ proportional to `x^2`, `x` and constants.
56
+
57
+ Examples
58
+ ========
59
+
60
+ >>> from sympy import O, oo, cos, pi
61
+ >>> from sympy.abc import x, y
62
+
63
+ >>> O(x + x**2)
64
+ O(x)
65
+ >>> O(x + x**2, (x, 0))
66
+ O(x)
67
+ >>> O(x + x**2, (x, oo))
68
+ O(x**2, (x, oo))
69
+
70
+ >>> O(1 + x*y)
71
+ O(1, x, y)
72
+ >>> O(1 + x*y, (x, 0), (y, 0))
73
+ O(1, x, y)
74
+ >>> O(1 + x*y, (x, oo), (y, oo))
75
+ O(x*y, (x, oo), (y, oo))
76
+
77
+ >>> O(1) in O(1, x)
78
+ True
79
+ >>> O(1, x) in O(1)
80
+ False
81
+ >>> O(x) in O(1, x)
82
+ True
83
+ >>> O(x**2) in O(x)
84
+ True
85
+
86
+ >>> O(x)*x
87
+ O(x**2)
88
+ >>> O(x) - O(x)
89
+ O(x)
90
+ >>> O(cos(x))
91
+ O(1)
92
+ >>> O(cos(x), (x, pi/2))
93
+ O(x - pi/2, (x, pi/2))
94
+
95
+ References
96
+ ==========
97
+
98
+ .. [1] `Big O notation <https://en.wikipedia.org/wiki/Big_O_notation>`_
99
+
100
+ Notes
101
+ =====
102
+
103
+ In ``O(f(x), x)`` the expression ``f(x)`` is assumed to have a leading
104
+ term. ``O(f(x), x)`` is automatically transformed to
105
+ ``O(f(x).as_leading_term(x),x)``.
106
+
107
+ ``O(expr*f(x), x)`` is ``O(f(x), x)``
108
+
109
+ ``O(expr, x)`` is ``O(1)``
110
+
111
+ ``O(0, x)`` is 0.
112
+
113
+ Multivariate O is also supported:
114
+
115
+ ``O(f(x, y), x, y)`` is transformed to
116
+ ``O(f(x, y).as_leading_term(x,y).as_leading_term(y), x, y)``
117
+
118
+ In the multivariate case, it is assumed the limits w.r.t. the various
119
+ symbols commute.
120
+
121
+ If no symbols are passed then all symbols in the expression are used
122
+ and the limit point is assumed to be zero.
123
+
124
+ """
125
+
126
+ is_Order = True
127
+
128
+ __slots__ = ()
129
+
130
+ @cacheit
131
+ def __new__(cls, expr, *args, **kwargs):
132
+ expr = sympify(expr)
133
+
134
+ if not args:
135
+ if expr.is_Order:
136
+ variables = expr.variables
137
+ point = expr.point
138
+ else:
139
+ variables = list(expr.free_symbols)
140
+ point = [S.Zero]*len(variables)
141
+ else:
142
+ args = list(args if is_sequence(args) else [args])
143
+ variables, point = [], []
144
+ if is_sequence(args[0]):
145
+ for a in args:
146
+ v, p = list(map(sympify, a))
147
+ variables.append(v)
148
+ point.append(p)
149
+ else:
150
+ variables = list(map(sympify, args))
151
+ point = [S.Zero]*len(variables)
152
+
153
+ if not all(v.is_symbol for v in variables):
154
+ raise TypeError('Variables are not symbols, got %s' % variables)
155
+
156
+ if len(list(uniq(variables))) != len(variables):
157
+ raise ValueError('Variables are supposed to be unique symbols, got %s' % variables)
158
+
159
+ if expr.is_Order:
160
+ expr_vp = dict(expr.args[1:])
161
+ new_vp = dict(expr_vp)
162
+ vp = dict(zip(variables, point))
163
+ for v, p in vp.items():
164
+ if v in new_vp.keys():
165
+ if p != new_vp[v]:
166
+ raise NotImplementedError(
167
+ "Mixing Order at different points is not supported.")
168
+ else:
169
+ new_vp[v] = p
170
+ if set(expr_vp.keys()) == set(new_vp.keys()):
171
+ return expr
172
+ else:
173
+ variables = list(new_vp.keys())
174
+ point = [new_vp[v] for v in variables]
175
+
176
+ if expr is S.NaN:
177
+ return S.NaN
178
+
179
+ if any(x in p.free_symbols for x in variables for p in point):
180
+ raise ValueError('Got %s as a point.' % point)
181
+
182
+ if variables:
183
+ if any(p != point[0] for p in point):
184
+ raise NotImplementedError(
185
+ "Multivariable orders at different points are not supported.")
186
+ if point[0] in (S.Infinity, S.Infinity*S.ImaginaryUnit):
187
+ s = {k: 1/Dummy() for k in variables}
188
+ rs = {1/v: 1/k for k, v in s.items()}
189
+ ps = [S.Zero for p in point]
190
+ elif point[0] in (S.NegativeInfinity, S.NegativeInfinity*S.ImaginaryUnit):
191
+ s = {k: -1/Dummy() for k in variables}
192
+ rs = {-1/v: -1/k for k, v in s.items()}
193
+ ps = [S.Zero for p in point]
194
+ elif point[0] is not S.Zero:
195
+ s = {k: Dummy() + point[0] for k in variables}
196
+ rs = {(v - point[0]).together(): k - point[0] for k, v in s.items()}
197
+ ps = [S.Zero for p in point]
198
+ else:
199
+ s = ()
200
+ rs = ()
201
+ ps = list(point)
202
+
203
+ expr = expr.subs(s)
204
+
205
+ if expr.is_Add:
206
+ expr = expr.factor()
207
+
208
+ if s:
209
+ args = tuple([r[0] for r in rs.items()])
210
+ else:
211
+ args = tuple(variables)
212
+
213
+ if len(variables) > 1:
214
+ # XXX: better way? We need this expand() to
215
+ # workaround e.g: expr = x*(x + y).
216
+ # (x*(x + y)).as_leading_term(x, y) currently returns
217
+ # x*y (wrong order term!). That's why we want to deal with
218
+ # expand()'ed expr (handled in "if expr.is_Add" branch below).
219
+ expr = expr.expand()
220
+
221
+ old_expr = None
222
+ while old_expr != expr:
223
+ old_expr = expr
224
+ if expr.is_Add:
225
+ lst = expr.extract_leading_order(args)
226
+ expr = Add(*[f.expr for (e, f) in lst])
227
+
228
+ elif expr:
229
+ try:
230
+ expr = expr.as_leading_term(*args)
231
+ except PoleError:
232
+ if isinstance(expr, Function) or\
233
+ all(isinstance(arg, Function) for arg in expr.args):
234
+ # It is not possible to simplify an expression
235
+ # containing only functions (which raise error on
236
+ # call to leading term) further
237
+ pass
238
+ else:
239
+ orders = []
240
+ pts = tuple(zip(args, ps))
241
+ for arg in expr.args:
242
+ try:
243
+ lt = arg.as_leading_term(*args)
244
+ except PoleError:
245
+ lt = arg
246
+ if lt not in args:
247
+ order = Order(lt)
248
+ else:
249
+ order = Order(lt, *pts)
250
+ orders.append(order)
251
+ if expr.is_Add:
252
+ new_expr = Order(Add(*orders), *pts)
253
+ if new_expr.is_Add:
254
+ new_expr = Order(Add(*[a.expr for a in new_expr.args]), *pts)
255
+ expr = new_expr.expr
256
+ elif expr.is_Mul:
257
+ expr = Mul(*[a.expr for a in orders])
258
+ elif expr.is_Pow:
259
+ e = expr.exp
260
+ b = expr.base
261
+ expr = exp(e * log(b))
262
+
263
+ # It would probably be better to handle this somewhere
264
+ # else. This is needed for a testcase in which there is a
265
+ # symbol with the assumptions zero=True.
266
+ if expr.is_zero:
267
+ expr = S.Zero
268
+ else:
269
+ expr = expr.as_independent(*args, as_Add=False)[1]
270
+
271
+ expr = expand_power_base(expr)
272
+ expr = expand_log(expr)
273
+
274
+ if len(args) == 1:
275
+ # The definition of O(f(x)) symbol explicitly stated that
276
+ # the argument of f(x) is irrelevant. That's why we can
277
+ # combine some power exponents (only "on top" of the
278
+ # expression tree for f(x)), e.g.:
279
+ # x**p * (-x)**q -> x**(p+q) for real p, q.
280
+ x = args[0]
281
+ margs = list(Mul.make_args(
282
+ expr.as_independent(x, as_Add=False)[1]))
283
+
284
+ for i, t in enumerate(margs):
285
+ if t.is_Pow:
286
+ b, q = t.args
287
+ if b in (x, -x) and q.is_real and not q.has(x):
288
+ margs[i] = x**q
289
+ elif b.is_Pow and not b.exp.has(x):
290
+ b, r = b.args
291
+ if b in (x, -x) and r.is_real:
292
+ margs[i] = x**(r*q)
293
+ elif b.is_Mul and b.args[0] is S.NegativeOne:
294
+ b = -b
295
+ if b.is_Pow and not b.exp.has(x):
296
+ b, r = b.args
297
+ if b in (x, -x) and r.is_real:
298
+ margs[i] = x**(r*q)
299
+
300
+ expr = Mul(*margs)
301
+
302
+ expr = expr.subs(rs)
303
+
304
+ if expr.is_Order:
305
+ expr = expr.expr
306
+
307
+ if not expr.has(*variables) and not expr.is_zero:
308
+ expr = S.One
309
+
310
+ # create Order instance:
311
+ vp = dict(zip(variables, point))
312
+ variables.sort(key=default_sort_key)
313
+ point = [vp[v] for v in variables]
314
+ args = (expr,) + Tuple(*zip(variables, point))
315
+ obj = Expr.__new__(cls, *args)
316
+ return obj
317
+
318
+ def _eval_nseries(self, x, n, logx, cdir=0):
319
+ return self
320
+
321
+ @property
322
+ def expr(self):
323
+ return self.args[0]
324
+
325
+ @property
326
+ def variables(self):
327
+ if self.args[1:]:
328
+ return tuple(x[0] for x in self.args[1:])
329
+ else:
330
+ return ()
331
+
332
+ @property
333
+ def point(self):
334
+ if self.args[1:]:
335
+ return tuple(x[1] for x in self.args[1:])
336
+ else:
337
+ return ()
338
+
339
+ @property
340
+ def free_symbols(self):
341
+ return self.expr.free_symbols | set(self.variables)
342
+
343
+ def _eval_power(b, e):
344
+ if e.is_Number and e.is_nonnegative:
345
+ return b.func(b.expr ** e, *b.args[1:])
346
+ if e == O(1):
347
+ return b
348
+ return
349
+
350
+ def as_expr_variables(self, order_symbols):
351
+ if order_symbols is None:
352
+ order_symbols = self.args[1:]
353
+ else:
354
+ if (not all(o[1] == order_symbols[0][1] for o in order_symbols) and
355
+ not all(p == self.point[0] for p in self.point)): # pragma: no cover
356
+ raise NotImplementedError('Order at points other than 0 '
357
+ 'or oo not supported, got %s as a point.' % self.point)
358
+ if order_symbols and order_symbols[0][1] != self.point[0]:
359
+ raise NotImplementedError(
360
+ "Multiplying Order at different points is not supported.")
361
+ order_symbols = dict(order_symbols)
362
+ for s, p in dict(self.args[1:]).items():
363
+ if s not in order_symbols.keys():
364
+ order_symbols[s] = p
365
+ order_symbols = sorted(order_symbols.items(), key=lambda x: default_sort_key(x[0]))
366
+ return self.expr, tuple(order_symbols)
367
+
368
+ def removeO(self):
369
+ return S.Zero
370
+
371
+ def getO(self):
372
+ return self
373
+
374
+ @cacheit
375
+ def contains(self, expr):
376
+ r"""
377
+ Return True if expr belongs to Order(self.expr, \*self.variables).
378
+ Return False if self belongs to expr.
379
+ Return None if the inclusion relation cannot be determined
380
+ (e.g. when self and expr have different symbols).
381
+ """
382
+ expr = sympify(expr)
383
+ if expr.is_zero:
384
+ return True
385
+ if expr is S.NaN:
386
+ return False
387
+ point = self.point[0] if self.point else S.Zero
388
+ if expr.is_Order:
389
+ if (any(p != point for p in expr.point) or
390
+ any(p != point for p in self.point)):
391
+ return None
392
+ if expr.expr == self.expr:
393
+ # O(1) + O(1), O(1) + O(1, x), etc.
394
+ return all(x in self.args[1:] for x in expr.args[1:])
395
+ if expr.expr.is_Add:
396
+ return all(self.contains(x) for x in expr.expr.args)
397
+ if self.expr.is_Add and point.is_zero:
398
+ return any(self.func(x, *self.args[1:]).contains(expr)
399
+ for x in self.expr.args)
400
+ if self.variables and expr.variables:
401
+ common_symbols = tuple(
402
+ [s for s in self.variables if s in expr.variables])
403
+ elif self.variables:
404
+ common_symbols = self.variables
405
+ else:
406
+ common_symbols = expr.variables
407
+ if not common_symbols:
408
+ return None
409
+ if (self.expr.is_Pow and len(self.variables) == 1
410
+ and self.variables == expr.variables):
411
+ symbol = self.variables[0]
412
+ other = expr.expr.as_independent(symbol, as_Add=False)[1]
413
+ if (other.is_Pow and other.base == symbol and
414
+ self.expr.base == symbol):
415
+ if point.is_zero:
416
+ rv = (self.expr.exp - other.exp).is_nonpositive
417
+ if point.is_infinite:
418
+ rv = (self.expr.exp - other.exp).is_nonnegative
419
+ if rv is not None:
420
+ return rv
421
+
422
+ from sympy.simplify.powsimp import powsimp
423
+ r = None
424
+ ratio = self.expr/expr.expr
425
+ ratio = powsimp(ratio, deep=True, combine='exp')
426
+ for s in common_symbols:
427
+ from sympy.series.limits import Limit
428
+ l = Limit(ratio, s, point).doit(heuristics=False)
429
+ if not isinstance(l, Limit):
430
+ l = l != 0
431
+ else:
432
+ l = None
433
+ if r is None:
434
+ r = l
435
+ else:
436
+ if r != l:
437
+ return
438
+ return r
439
+
440
+ if self.expr.is_Pow and len(self.variables) == 1:
441
+ symbol = self.variables[0]
442
+ other = expr.as_independent(symbol, as_Add=False)[1]
443
+ if (other.is_Pow and other.base == symbol and
444
+ self.expr.base == symbol):
445
+ if point.is_zero:
446
+ rv = (self.expr.exp - other.exp).is_nonpositive
447
+ if point.is_infinite:
448
+ rv = (self.expr.exp - other.exp).is_nonnegative
449
+ if rv is not None:
450
+ return rv
451
+
452
+ obj = self.func(expr, *self.args[1:])
453
+ return self.contains(obj)
454
+
455
+ def __contains__(self, other):
456
+ result = self.contains(other)
457
+ if result is None:
458
+ raise TypeError('contains did not evaluate to a bool')
459
+ return result
460
+
461
+ def _eval_subs(self, old, new):
462
+ if old in self.variables:
463
+ newexpr = self.expr.subs(old, new)
464
+ i = self.variables.index(old)
465
+ newvars = list(self.variables)
466
+ newpt = list(self.point)
467
+ if new.is_symbol:
468
+ newvars[i] = new
469
+ else:
470
+ syms = new.free_symbols
471
+ if len(syms) == 1 or old in syms:
472
+ if old in syms:
473
+ var = self.variables[i]
474
+ else:
475
+ var = syms.pop()
476
+ # First, try to substitute self.point in the "new"
477
+ # expr to see if this is a fixed point.
478
+ # E.g. O(y).subs(y, sin(x))
479
+ point = new.subs(var, self.point[i])
480
+ if point != self.point[i]:
481
+ from sympy.solvers.solveset import solveset
482
+ d = Dummy()
483
+ sol = solveset(old - new.subs(var, d), d)
484
+ if isinstance(sol, Complement):
485
+ e1 = sol.args[0]
486
+ e2 = sol.args[1]
487
+ sol = set(e1) - set(e2)
488
+ res = [dict(zip((d, ), sol))]
489
+ point = d.subs(res[0]).limit(old, self.point[i])
490
+ newvars[i] = var
491
+ newpt[i] = point
492
+ elif old not in syms:
493
+ del newvars[i], newpt[i]
494
+ if not syms and new == self.point[i]:
495
+ newvars.extend(syms)
496
+ newpt.extend([S.Zero]*len(syms))
497
+ else:
498
+ return
499
+ return Order(newexpr, *zip(newvars, newpt))
500
+
501
+ def _eval_conjugate(self):
502
+ expr = self.expr._eval_conjugate()
503
+ if expr is not None:
504
+ return self.func(expr, *self.args[1:])
505
+
506
+ def _eval_derivative(self, x):
507
+ return self.func(self.expr.diff(x), *self.args[1:]) or self
508
+
509
+ def _eval_transpose(self):
510
+ expr = self.expr._eval_transpose()
511
+ if expr is not None:
512
+ return self.func(expr, *self.args[1:])
513
+
514
+ def __neg__(self):
515
+ return self
516
+
517
+ O = Order
evalkit_internvl/lib/python3.10/site-packages/sympy/series/residues.py ADDED
@@ -0,0 +1,73 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ """
2
+ This module implements the Residue function and related tools for working
3
+ with residues.
4
+ """
5
+
6
+ from sympy.core.mul import Mul
7
+ from sympy.core.singleton import S
8
+ from sympy.core.sympify import sympify
9
+ from sympy.utilities.timeutils import timethis
10
+
11
+
12
+ @timethis('residue')
13
+ def residue(expr, x, x0):
14
+ """
15
+ Finds the residue of ``expr`` at the point x=x0.
16
+
17
+ The residue is defined as the coefficient of ``1/(x-x0)`` in the power series
18
+ expansion about ``x=x0``.
19
+
20
+ Examples
21
+ ========
22
+
23
+ >>> from sympy import Symbol, residue, sin
24
+ >>> x = Symbol("x")
25
+ >>> residue(1/x, x, 0)
26
+ 1
27
+ >>> residue(1/x**2, x, 0)
28
+ 0
29
+ >>> residue(2/sin(x), x, 0)
30
+ 2
31
+
32
+ This function is essential for the Residue Theorem [1].
33
+
34
+ References
35
+ ==========
36
+
37
+ .. [1] https://en.wikipedia.org/wiki/Residue_theorem
38
+ """
39
+ # The current implementation uses series expansion to
40
+ # calculate it. A more general implementation is explained in
41
+ # the section 5.6 of the Bronstein's book {M. Bronstein:
42
+ # Symbolic Integration I, Springer Verlag (2005)}. For purely
43
+ # rational functions, the algorithm is much easier. See
44
+ # sections 2.4, 2.5, and 2.7 (this section actually gives an
45
+ # algorithm for computing any Laurent series coefficient for
46
+ # a rational function). The theory in section 2.4 will help to
47
+ # understand why the resultant works in the general algorithm.
48
+ # For the definition of a resultant, see section 1.4 (and any
49
+ # previous sections for more review).
50
+
51
+ from sympy.series.order import Order
52
+ from sympy.simplify.radsimp import collect
53
+ expr = sympify(expr)
54
+ if x0 != 0:
55
+ expr = expr.subs(x, x + x0)
56
+ for n in (0, 1, 2, 4, 8, 16, 32):
57
+ s = expr.nseries(x, n=n)
58
+ if not s.has(Order) or s.getn() >= 0:
59
+ break
60
+ s = collect(s.removeO(), x)
61
+ if s.is_Add:
62
+ args = s.args
63
+ else:
64
+ args = [s]
65
+ res = S.Zero
66
+ for arg in args:
67
+ c, m = arg.as_coeff_mul(x)
68
+ m = Mul(*m)
69
+ if not (m in (S.One, x) or (m.is_Pow and m.exp.is_Integer)):
70
+ raise NotImplementedError('term of unexpected form: %s' % m)
71
+ if m == 1/x:
72
+ res += c
73
+ return res