Update src/streamlit_app.py

src/streamlit_app.py

@@ -80,13 +80,24 @@ st.markdown("""
 def main():
     st.markdown('<div class="main-header">🚀 Physics Tutorial: Kinematics</div>', unsafe_allow_html=True)
     
+    # Use session state to prevent unnecessary reruns
+    if 'current_tab' not in st.session_state:
+        st.session_state.current_tab = "1D Motion"
+    
     # Sidebar for navigation
     st.sidebar.title("📚 Select Tutorial")
     tutorial_type = st.sidebar.radio(
         "Choose a physics concept:",
-        ["1D Motion", "2D Projectile Motion", "Compare Motions"]
+        ["1D Motion", "2D Projectile Motion", "Compare Motions"],
+        index=["1D Motion", "2D Projectile Motion", "Compare Motions"].index(st.session_state.current_tab)
     )
     
+    # Only trigger rerun if tab actually changed
+    if tutorial_type != st.session_state.current_tab:
+        st.session_state.current_tab = tutorial_type
+        # Clear matplotlib plots when switching tabs
+        plt.close('all')
+    
     if tutorial_type == "1D Motion":
         show_1d_motion()
     elif tutorial_type == "2D Projectile Motion":