Update app.py

app.py

@@ -226,17 +226,23 @@ def neural_networks():
 # Sidebar for content navigation
 st.sidebar.header("📚 Contents")
 
-# Show Introduction first in the sidebar
-intro_option = st.sidebar.radio("📚 Introduction", ["Introduction", "Select a Topic"])
+# Show Introduction first in the sidebar (Only display the Introduction option initially)
+intro_option = st.sidebar.radio("📚 Introduction", ["Introduction", "Select a Topic"], index=0)
 
-# Grouping the types of machine learning into one section
-types_of_ml = st.sidebar.radio("📊 Types of Machine Learning", 
-                               ["Select a Type", "Supervised Learning", "Unsupervised Learning", "Reinforcement Learning"])
+# Grouping the types of machine learning into one section (Only after Introduction is selected)
+if intro_option == "Introduction":
+    types_of_ml = st.sidebar.radio("📊 Types of Machine Learning", 
+                                   ["Supervised Learning", "Unsupervised Learning", "Reinforcement Learning"])
+else:
+    types_of_ml = None
 
-# Grouping other topics under a separate section
-popular_algorithms = st.sidebar.radio("🚀 Popular Algorithms", 
-                                      ["Select an Algorithm", "Linear Regression", "Logistic Regression", "Decision Trees", 
-                                       "K-Nearest Neighbors (KNN)", "Support Vector Machines (SVM)", "Neural Networks"])
+# Grouping other topics under a separate section (Only after Introduction is selected)
+if intro_option == "Introduction":
+    popular_algorithms = st.sidebar.radio("🚀 Popular Algorithms", 
+                                          ["Linear Regression", "Logistic Regression", "Decision Trees", 
+                                           "K-Nearest Neighbors (KNN)", "Support Vector Machines (SVM)", "Neural Networks"])
+else:
+    popular_algorithms = None
 
 # Mapping page functions to selection
 pages = {
@@ -254,18 +260,18 @@ pages = {
 # Main content area
 st.markdown("<h1 style='text-align: center; color: orange;'>Machine Learning (ML)</h1>", unsafe_allow_html=True)
 
-# Show the Introduction content first
+# Show the Introduction content first (Only show if selected)
 if intro_option == "Introduction":
     st.markdown(introduction_to_ml())
 
 # Show content based on the selected type of machine learning or algorithm from the sidebar
-if types_of_ml != "Select a Type":
+if types_of_ml:
     st.markdown(f"<h2 style='text-align: center; color: orange;'>{types_of_ml}</h2>", unsafe_allow_html=True)
     content_function = pages.get(types_of_ml, None)
     if content_function:
         st.markdown(content_function())
 
-if popular_algorithms != "Select an Algorithm":
+if popular_algorithms:
     st.markdown(f"<h2 style='text-align: center; color: orange;'>{popular_algorithms}</h2>", unsafe_allow_html=True)
     content_function = pages.get(popular_algorithms, None)
     if content_function: