added buttons for navigation

app.py

@@ -80,6 +80,18 @@ def make_plots(idx: int):
     
     return figs
 
+def button_previous(idx: int) -> int:
+    if idx == 1:
+        return N
+
+    return idx-1    
+    
+def button_next(idx: int) -> int:
+    if idx == N:
+        return 1
+
+    return idx+1
+
 
 def demo():
     fig_1, fig_2, fig_3, fig_4 = make_plots(0)
@@ -98,10 +110,16 @@ def demo():
                 result_4 = gr.Plot(value=fig_4, label="SNR 20 dB")
             
         with gr.Row():
-            slider = gr.Slider(1, N, 1, label="Sample Index")
+            previous = gr.Button(value="< Previous")
+            next = gr.Button(value="Next >")
+        
+        with gr.Row():
+            slider = gr.Slider(1, N, 1, label="Sample Index (Snapshot)")
             
         # update callbacks
         slider.change(make_plots, [slider], [result_1, result_2, result_3, result_4])
+        previous.click(button_previous, [slider], [slider])
+        next.click(button_next, [slider], [slider])
         
         gr.Markdown(
             TEXTS.acknowledgements