Update app.py

app.py

@@ -2,10 +2,6 @@ import streamlit as st
 import matplotlib.pyplot as plt
 import networkx as nx
 
-# Initialize session state variable if it does not exist
-if 'graph_displayed' not in st.session_state:
-    st.session_state.graph_displayed = False
-
 # Sidebar for selecting an option
 sidebar_option = st.sidebar.radio("Select an option", 
                                  ["Select an option", "Basic: Properties", 
@@ -81,7 +77,7 @@ def display_read_write_graph(G):
     st.pyplot(plt)
 
 # Function to display Simple Graphs for Basic: Simple graph
-def display_simple_graph(G, pos=None, directed=False):
+def display_simple_graph(G, pos=None):
     options = {
         "font_size": 36,
         "node_size": 3000,
@@ -92,10 +88,7 @@ def display_simple_graph(G, pos=None, directed=False):
     }
     
     # Draw the network
-    if directed:
-        nx.draw_networkx(G, pos, **options, arrows=True)  # For directed graph with arrows
-    else:
-        nx.draw_networkx(G, pos, **options)
+    nx.draw_networkx(G, pos, **options)
 
     # Set margins for the axes so that nodes aren't clipped
     ax = plt.gca()
@@ -164,24 +157,6 @@ elif sidebar_option == "Basic: Simple graph":
         pos = {1: (0, 0), 2: (-1, 0.3), 3: (2, 0.17), 4: (4, 0.255), 5: (5, 0.03)}
         display_simple_graph(G, pos)
 
-    # Default example: directed graph with custom positions (added the missing part)
-    if option == "Default Example" and not st.session_state.graph_displayed:
-        G = nx.DiGraph([(0, 3), (1, 3), (2, 4), (3, 5), (3, 6), (4, 6), (5, 6)])
-
-        # Group nodes by column
-        left_nodes = [0, 1, 2]
-        middle_nodes = [3, 4]
-        right_nodes = [5, 6]
-
-        # Set the position according to column (x-coordinates)
-        pos = {n: (0, i) for i, n in enumerate(left_nodes)}
-        pos.update({n: (1, i + 0.5) for i, n in enumerate(middle_nodes)})
-        pos.update({n: (2, i + 0.5) for i, n in enumerate(right_nodes)})
-
-        # Visualize the directed graph
-        display_simple_graph(G, pos, directed=True)
-        st.session_state.graph_displayed = True
-        
     # Create your own graph
     elif option == "Create your own":
         num_nodes = st.number_input("Number of nodes:", min_value=2, max_value=20, value=5)
@@ -205,4 +180,4 @@ elif sidebar_option == "Basic: Simple graph":
             
             # Set a basic layout (spring layout as default)
             pos = nx.spring_layout(G_custom, seed=42)
-            display_simple_graph(G_custom, pos)
+            display_simple_graph(G_custom, pos)