Update app.py

app.py

@@ -76,42 +76,46 @@ def display_tsp():
         num_nodes = st.slider("Number of nodes:", min_value=3, max_value=30, value=20)
         radius = st.slider("Edge radius:", min_value=0.1, max_value=1.0, value=0.4)
 
-        # Create random geometric graph based on user input
-        G_custom = nx.random_geometric_graph(num_nodes, radius, seed=3)
-        pos = nx.get_node_attributes(G_custom, "pos")
+        # Add a button to generate a new graph
+        generate_button = st.button("Generate Graph")
 
-        # Depot should be at (0.5, 0.5)
-        pos[0] = (0.5, 0.5)
+        if generate_button:
+            # Create random geometric graph based on user input
+            G_custom = nx.random_geometric_graph(num_nodes, radius, seed=3)
+            pos = nx.get_node_attributes(G_custom, "pos")
 
-        H = G_custom.copy()
+            # Depot should be at (0.5, 0.5)
+            pos[0] = (0.5, 0.5)
 
-        # Calculating the distances between the nodes as edge's weight.
-        for i in range(len(pos)):
-            for j in range(i + 1, len(pos)):
-                dist = math.hypot(pos[i][0] - pos[j][0], pos[i][1] - pos[j][1])
-                dist = dist
-                G_custom.add_edge(i, j, weight=dist)
+            H = G_custom.copy()
 
-        # Find TSP cycle using Christofides' approximation
-        cycle = christofides(G_custom, weight="weight")
-        edge_list = list(nx.utils.pairwise(cycle))
+            # Calculating the distances between the nodes as edge's weight.
+            for i in range(len(pos)):
+                for j in range(i + 1, len(pos)):
+                    dist = math.hypot(pos[i][0] - pos[j][0], pos[i][1] - pos[j][1])
+                    dist = dist
+                    G_custom.add_edge(i, j, weight=dist)
 
-        # Draw closest edges on each node only
-        nx.draw_networkx_edges(H, pos, edge_color="blue", width=0.5)
+            # Find TSP cycle using Christofides' approximation
+            cycle = christofides(G_custom, weight="weight")
+            edge_list = list(nx.utils.pairwise(cycle))
 
-        # Draw the TSP route
-        nx.draw_networkx(
-            G_custom,
-            pos,
-            with_labels=True,
-            edgelist=edge_list,
-            edge_color="red",
-            node_size=200,
-            width=3,
-        )
+            # Draw closest edges on each node only
+            nx.draw_networkx_edges(H, pos, edge_color="blue", width=0.5)
 
-        st.pyplot(plt)
-        st.write("The route of the traveler is:", cycle)
+            # Draw the TSP route
+            nx.draw_networkx(
+                G_custom,
+                pos,
+                with_labels=True,
+                edgelist=edge_list,
+                edge_color="red",
+                node_size=200,
+                width=3,
+            )
+
+            st.pyplot(plt)
+            st.write("The route of the traveler is:", cycle)
 
 # Display Drawing: Traveling Salesman Problem if selected
 if sidebar_option == "Drawing: Traveling Salesman Problem":