Update src/streamlit_app.py

src/streamlit_app.py

@@ -3,6 +3,13 @@ import numpy as np
 import matplotlib.pyplot as plt
 from kinematics_visualizer import Motion1D, Motion2D, KinematicsVisualizer
 
+def clear_comparison_state():
+    """Clear any lingering comparison state"""
+    keys_to_clear = [key for key in st.session_state.keys() if key.startswith('comp_')]
+    for key in keys_to_clear:
+        if key in st.session_state:
+            del st.session_state[key]
+
 # Configure Streamlit page
 st.set_page_config(
     page_title="Physics Tutorial: Kinematics",
@@ -68,6 +75,11 @@ def main():
         ["1D Motion", "2D Projectile Motion", "Compare Motions"]
     )
     
+    # Clear comparison state when not on comparison tab
+    if tutorial_type != "Compare Motions":
+        clear_comparison_state()
+        plt.close('all')  # Close any lingering plots
+    
     if tutorial_type == "1D Motion":
         show_1d_motion()
     elif tutorial_type == "2D Projectile Motion":
@@ -473,86 +485,124 @@ def show_motion_comparison():
     
     st.markdown("**Compare up to 3 different projectile motions side by side**")
     
+    # Clear any previous matplotlib figures explicitly
+    plt.clf()
+    plt.close('all')
+    
     # Create tabs for different trajectories
     tab1, tab2, tab3 = st.tabs(["🚀 Trajectory 1", "🎯 Trajectory 2", "⚽ Trajectory 3"])
     
     trajectories = []
     
+    # Use containers to isolate each tab's content
     with tab1:
-        col1, col2 = st.columns(2)
-        with col1:
-            speed1 = st.slider("Speed 1 (m/s)", 5.0, 50.0, 20.0, key="speed1")
-            angle1 = st.slider("Angle 1 (°)", 0.0, 90.0, 30.0, key="angle1")
-        with col2:
-            height1 = st.slider("Height 1 (m)", 0.0, 30.0, 0.0, key="height1")
-            
-        motion1 = Motion2D(launch_speed=speed1, launch_angle=angle1, launch_height=height1)
-        trajectories.append(("Trajectory 1", motion1, 'blue'))
+        with st.container():
+            col1, col2 = st.columns(2)
+            with col1:
+                speed1 = st.slider("Speed 1 (m/s)", 5.0, 50.0, 20.0, key="comp_speed1")
+                angle1 = st.slider("Angle 1 (°)", 0.0, 90.0, 30.0, key="comp_angle1")
+            with col2:
+                height1 = st.slider("Height 1 (m)", 0.0, 30.0, 0.0, key="comp_height1")
+                
+            motion1 = Motion2D(launch_speed=speed1, launch_angle=angle1, launch_height=height1)
+            trajectories.append(("Trajectory 1", motion1, 'blue'))
     
     with tab2:
-        col1, col2 = st.columns(2)
-        with col1:
-            speed2 = st.slider("Speed 2 (m/s)", 5.0, 50.0, 25.0, key="speed2")
-            angle2 = st.slider("Angle 2 (°)", 0.0, 90.0, 45.0, key="angle2")
-        with col2:
-            height2 = st.slider("Height 2 (m)", 0.0, 30.0, 0.0, key="height2")
-            
-        motion2 = Motion2D(launch_speed=speed2, launch_angle=angle2, launch_height=height2)
-        trajectories.append(("Trajectory 2", motion2, 'red'))
+        with st.container():
+            col1, col2 = st.columns(2)
+            with col1:
+                speed2 = st.slider("Speed 2 (m/s)", 5.0, 50.0, 25.0, key="comp_speed2")
+                angle2 = st.slider("Angle 2 (°)", 0.0, 90.0, 45.0, key="comp_angle2")
+            with col2:
+                height2 = st.slider("Height 2 (m)", 0.0, 30.0, 0.0, key="comp_height2")
+                
+            motion2 = Motion2D(launch_speed=speed2, launch_angle=angle2, launch_height=height2)
+            trajectories.append(("Trajectory 2", motion2, 'red'))
     
     with tab3:
-        col1, col2 = st.columns(2)
-        with col1:
-            speed3 = st.slider("Speed 3 (m/s)", 5.0, 50.0, 30.0, key="speed3")
-            angle3 = st.slider("Angle 3 (°)", 0.0, 90.0, 60.0, key="angle3")
-        with col2:
-            height3 = st.slider("Height 3 (m)", 0.0, 30.0, 5.0, key="height3")
-            
-        motion3 = Motion2D(launch_speed=speed3, launch_angle=angle3, launch_height=height3)
-        trajectories.append(("Trajectory 3", motion3, 'green'))
-    
-    # Create comparison plot
-    fig, ax = plt.subplots(figsize=(12, 8))
-    
-    max_range = 0
-    for name, motion, color in trajectories:
-        data = motion.trajectory_data(motion.calculate_flight_time())
-        ax.plot(data['x'], data['y'], linewidth=3, label=name, color=color)
-        
-        # Mark launch and landing points
-        ax.plot(motion.launch_x, motion.launch_height, 'o', markersize=8, color=color, alpha=0.7)
-        if len(data['x']) > 0:
-            ax.plot(data['x'][-1], data['y'][-1], 's', markersize=8, color=color, alpha=0.7)
-            max_range = max(max_range, data['x'][-1])
+        with st.container():
+            col1, col2 = st.columns(2)
+            with col1:
+                speed3 = st.slider("Speed 3 (m/s)", 5.0, 50.0, 30.0, key="comp_speed3")
+                angle3 = st.slider("Angle 3 (°)", 0.0, 90.0, 60.0, key="comp_angle3")
+            with col2:
+                height3 = st.slider("Height 3 (m)", 0.0, 30.0, 5.0, key="comp_height3")
+                
+            motion3 = Motion2D(launch_speed=speed3, launch_angle=angle3, launch_height=height3)
+            trajectories.append(("Trajectory 3", motion3, 'green'))
     
-    ax.set_xlabel('Horizontal Position (m)', fontsize=12)
-    ax.set_ylabel('Vertical Position (m)', fontsize=12)
-    ax.set_title('Trajectory Comparison', fontsize=16, fontweight='bold')
-    ax.grid(True, alpha=0.3)
-    ax.legend(fontsize=12)
-    ax.set_ylim(bottom=0)
-    ax.set_xlim(0, max_range * 1.1)
-    
-    st.pyplot(fig)
-    plt.close()
-    
-    # Comparison table
-    st.markdown("### 📋 Trajectory Comparison Table")
-    
-    comparison_data = []
-    for name, motion, _ in trajectories:
-        info = motion.get_launch_info()
-        comparison_data.append({
-            "Trajectory": name,
-            "Speed (m/s)": f"{info['launch_speed']:.1f}",
-            "Angle (°)": f"{info['launch_angle']:.1f}",
-            "Height (m)": f"{info['launch_height']:.1f}",
-            "Flight Time (s)": f"{info['flight_time']:.2f}",
-            "Range (m)": f"{info['range']:.1f}",
-            "Max Height (m)": f"{info['max_height']:.1f}"
-        })
+    # Create comparison plot in its own container
+    with st.container():
+        try:
+            # Ensure we have a clean figure
+            plt.close('all')
+            fig, ax = plt.subplots(figsize=(12, 8))
+            
+            max_range = 0
+            for name, motion, color in trajectories:
+                try:
+                    data = motion.trajectory_data(motion.calculate_flight_time())
+                    if len(data['x']) > 0:  # Check data exists
+                        ax.plot(data['x'], data['y'], linewidth=3, label=name, color=color)
+                        
+                        # Mark launch and landing points
+                        ax.plot(motion.launch_x, motion.launch_height, 'o', markersize=8, color=color, alpha=0.7)
+                        ax.plot(data['x'][-1], data['y'][-1], 's', markersize=8, color=color, alpha=0.7)
+                        max_range = max(max_range, data['x'][-1] if data['x'][-1] > 0 else 0)
+                except Exception as e:
+                    st.error(f"Error plotting {name}: {str(e)}")
+                    continue
+            
+            # Only proceed if we have valid data
+            if max_range > 0:
+                ax.set_xlabel('Horizontal Position (m)', fontsize=12)
+                ax.set_ylabel('Vertical Position (m)', fontsize=12)
+                ax.set_title('Trajectory Comparison', fontsize=16, fontweight='bold')
+                ax.grid(True, alpha=0.3)
+                ax.legend(fontsize=12)
+                ax.set_ylim(bottom=0)
+                ax.set_xlim(0, max_range * 1.1)
+                
+                # Display plot
+                st.pyplot(fig, clear_figure=True)  # Important: clear_figure=True
+            else:
+                st.warning("No valid trajectory data to display")
+                
+        except Exception as e:
+            st.error(f"Error creating comparison plot: {str(e)}")
+        finally:
+            plt.close(fig)  # Ensure figure is always closed
+            plt.close('all')
     
-    st.table(comparison_data)
+    # Comparison table in its own container
+    with st.container():
+        st.markdown("### 📋 Trajectory Comparison Table")
+        
+        try:
+            comparison_data = []
+            for name, motion, _ in trajectories:
+                try:
+                    info = motion.get_launch_info()
+                    comparison_data.append({
+                        "Trajectory": name,
+                        "Speed (m/s)": f"{info['launch_speed']:.1f}",
+                        "Angle (°)": f"{info['launch_angle']:.1f}",
+                        "Height (m)": f"{info['launch_height']:.1f}",
+                        "Flight Time (s)": f"{info['flight_time']:.2f}",
+                        "Range (m)": f"{info['range']:.1f}",
+                        "Max Height (m)": f"{info['max_height']:.1f}"
+                    })
+                except Exception as e:
+                    st.error(f"Error getting info for {name}: {str(e)}")
+                    continue
+            
+            if comparison_data:
+                st.table(comparison_data)
+            else:
+                st.warning("No trajectory data available for comparison table")
+                
+        except Exception as e:
+            st.error(f"Error creating comparison table: {str(e)}")
 
 if __name__ == "__main__":
     main()