Update app.py

app.py

@@ -39,6 +39,7 @@ docking_altitude_km = st.sidebar.number_input("Docking Altitude (km)", min_value
 run_sim = st.sidebar.button("Run Simulation")
 
 if run_sim:
+    st.info("Running simulation... Please wait.")
     # ===============================
     # Physical Constants and Conversions
     # ===============================
@@ -145,19 +146,25 @@ if run_sim:
         x_vals = states[:frame+1, 1] / 1000  # convert m to km
         y_vals = states[:frame+1, 2] / 1000  # convert m to km
         trajectory_line.set_data(x_vals, y_vals)
-        # Wrap the current marker coordinates in a list so they are interpreted as sequences:
+        # Wrap coordinates in a list so that they are interpreted as sequences:
         payload_marker.set_data([states[frame, 1] / 1000], [states[frame, 2] / 1000])
         time_text.set_text(f"Time: {t_val:.1f} s")
         return trajectory_line, payload_marker, time_text
 
-    # Create the animation. The interval (in ms) can be adjusted for speed.
+    # Create the animation. Adjust the interval (ms) for playback speed.
     anim = FuncAnimation(fig, update, frames=len(states), init_func=init, interval=20, blit=True)
 
     # Convert the animation to an HTML5 video.
     video_html = anim.to_html5_video()
 
-    st.markdown("### Simulation Animation")
-    components.html(video_html, height=500)
+    if video_html:
+        st.markdown("### Simulation Animation")
+        # Option 1: Use streamlit components to embed the HTML video
+        components.html(video_html, height=500)
+        # Option 2: Alternatively, use st.markdown (uncomment the following line to try it)
+        # st.markdown(video_html, unsafe_allow_html=True)
+    else:
+        st.error("No video generated. Please ensure that ffmpeg is installed and properly configured.")
 
     st.markdown(
         """