Update src/streamlit_app.py

src/streamlit_app.py

@@ -12,16 +12,20 @@ st.set_page_config(
 )
 
 # --- FDSN Client & Caching ---
-# Initialize the IRIS FDSN client
 client = Client("IRIS")
 
+# CORRECTED FUNCTION
 @st.cache_data
-def search_earthquakes(start_time, end_time, min_mag, min_lat, max_lat, min_lon, max_lon):
+def search_earthquakes(start_time_str, end_time_str, min_mag, min_lat, max_lat, min_lon, max_lon):
     """
     Searches for earthquake events using the ObsPy client.
-    Results are cached to prevent re-running the same query.
+    Accepts time as strings to enable caching.
     """
     try:
+        # Convert string arguments back to UTCDateTime objects inside the function
+        start_time = UTCDateTime(start_time_str)
+        end_time = UTCDateTime(end_time_str)
+        
         catalog = client.get_events(
             starttime=start_time,
             endtime=end_time,
@@ -30,7 +34,7 @@ def search_earthquakes(start_time, end_time, min_mag, min_lat, max_lat, min_lon,
             minlongitude=min_lon,
             maxlongitude=max_lon,
             minmagnitude=min_mag,
-            orderby="time-asc"  # Order by time, ascending
+            orderby="time-asc"
         )
         return catalog
     except Exception as e:
@@ -38,50 +42,39 @@ def search_earthquakes(start_time, end_time, min_mag, min_lat, max_lat, min_lon,
         return None
 
 @st.cache_data
-def get_waveforms_for_event(_event): # Caching requires hashable arguments
+def get_waveforms_for_event(_event):
     """
     Retrieves and processes seismic waveforms for a given event.
     _event is a tuple of event properties to make it hashable for caching.
     """
-    event_time_str, event_lat, event_lon, event_depth = _event
+    event_time_str, _, _, _ = _event
     event_time = UTCDateTime(event_time_str)
 
-    # Define a time window around the event origin time
-    t_start = event_time - 30  # 30 seconds before
-    t_end = event_time + 5 * 60   # 5 minutes after
+    t_start = event_time - 30
+    t_end = event_time + 5 * 60
 
     try:
-        # Fetch waveforms from the TW network for broadband channels
         stream = client.get_waveforms(
-            network="TW",
-            station="*",
-            location="*",
-            channel="BH*",  # Broadband High Gain channels (BHZ, BHN, BHE)
-            starttime=t_start,
-            endtime=t_end,
-            attach_response=True  # Attach instrument response
+            network="TW", station="*", location="*", channel="BH*",
+            starttime=t_start, endtime=t_end, attach_response=True
         )
         if len(stream) > 0:
-            # Pre-processing: Detrend, taper, and remove instrument response
             stream.detrend("linear")
             stream.taper(max_percentage=0.05, type="cosine")
-            stream.remove_response(output="VEL") # Convert to velocity (m/s)
+            stream.remove_response(output="VEL")
             return stream
         else:
             return None
     except Exception:
-        # Return None if no data is available or an error occurs
         return None
 
-
 # --- Streamlit User Interface ---
 st.title("🌋 Taiwan Earthquake Explorer")
 st.markdown("Search, map, and visualize seismic data from the TW network via IRIS FDSN.")
 
-# --- Sidebar for Search Controls ---
 st.sidebar.header("🔍 Search Parameters")
 
-# Date and Time Inputs
+# --- Sidebar Controls ---
 default_start = UTCDateTime("2024-04-02T23:00:00")
 default_end = UTCDateTime("2024-04-03T01:00:00")
 start_date = st.sidebar.date_input("Start Date", value=default_start.date)
@@ -89,11 +82,9 @@ start_time_str = st.sidebar.text_input("Start Time (UTC)", value=default_start.s
 end_date = st.sidebar.date_input("End Date", value=default_end.date)
 end_time_str = st.sidebar.text_input("End Time (UTC)", value=default_end.strftime("%H:%M:%S"))
 
-# Combine date and time
 start_utc = UTCDateTime(f"{start_date}T{start_time_str}")
 end_utc = UTCDateTime(f"{end_date}T{end_time_str}")
 
-# Magnitude and Location Inputs
 st.sidebar.markdown("---")
 min_mag = st.sidebar.slider("Minimum Magnitude", 2.0, 8.0, 5.5)
 
@@ -106,25 +97,20 @@ max_lon = st.sidebar.number_input("Max Longitude", value=122.5, format="%.2f")
 
 # --- Main App Logic ---
 if st.sidebar.button("Search for Earthquakes", type="primary"):
-    catalog = search_earthquakes(start_utc, end_utc, min_mag, min_lat, max_lat, min_lon, max_lon)
+    # CORRECTED FUNCTION CALL: Pass times as ISO strings
+    catalog = search_earthquakes(start_utc.isoformat(), end_utc.isoformat(), min_mag, min_lat, max_lat, min_lon, max_lon)
 
     if catalog and len(catalog) > 0:
         st.success(f"✅ Found {len(catalog)} earthquake(s).")
-
-        # --- Process and Display Data ---
-        event_data = []
-        for event in catalog:
-            origin = event.preferred_origin() or event.origins[0]
-            magnitude = event.preferred_magnitude() or event.magnitudes[0]
-            event_data.append({
-                "Time (UTC)": origin.time.strftime('%Y-%m-%d %H:%M:%S'),
-                "Latitude": origin.latitude,
-                "Longitude": origin.longitude,
-                "Depth (km)": origin.depth / 1000.0,
-                "Magnitude": magnitude.mag,
-                "Mag Type": magnitude.magnitude_type
-            })
-
+        
+        event_data = [{
+            "Time (UTC)": (event.preferred_origin() or event.origins[0]).time.strftime('%Y-%m-%d %H:%M:%S'),
+            "Latitude": (event.preferred_origin() or event.origins[0]).latitude,
+            "Longitude": (event.preferred_origin() or event.origins[0]).longitude,
+            "Depth (km)": (event.preferred_origin() or event.origins[0]).depth / 1000.0,
+            "Magnitude": (event.preferred_magnitude() or event.magnitudes[0]).mag,
+            "Mag Type": (event.preferred_magnitude() or event.magnitudes[0]).magnitude_type
+        } for event in catalog]
         event_df = pd.DataFrame(event_data)
 
         st.subheader("🗺️ Earthquake Map")
@@ -136,7 +122,6 @@ if st.sidebar.button("Search for Earthquakes", type="primary"):
         st.markdown("---")
         st.subheader(" seismograph Seismic Waveform Viewer")
 
-        # --- Waveform Selection and Display ---
         event_options = {f"{row['Time (UTC)']} - Mag: {row['Magnitude']:.1f}": index for index, row in event_df.iterrows()}
         selected_event_str = st.selectbox("Select an event to view waveforms:", options=event_options.keys())
 
@@ -145,20 +130,13 @@ if st.sidebar.button("Search for Earthquakes", type="primary"):
             selected_event = catalog[selected_index]
             origin = selected_event.preferred_origin() or selected_event.origins[0]
             
-            # Create a hashable tuple for caching
-            event_tuple = (
-                str(origin.time),
-                origin.latitude,
-                origin.longitude,
-                origin.depth
-            )
+            event_tuple = (str(origin.time), origin.latitude, origin.longitude, origin.depth)
 
             with st.spinner("Fetching waveforms from TW network... This may take a moment."):
                 waveforms = get_waveforms_for_event(event_tuple)
 
             if waveforms and len(waveforms) > 0:
                 st.success(f"📊 Found and processed {len(waveforms)} waveform traces.")
-                # Plotting the waveforms
                 fig, ax = plt.subplots(figsize=(12, len(waveforms) * 1.5))
                 waveforms.plot(fig=fig, handle=True)
                 ax.set_title(f"Seismic Waveforms for Event: {selected_event_str}")
@@ -168,3 +146,4 @@ if st.sidebar.button("Search for Earthquakes", type="primary"):
 
     else:
         st.warning("No earthquakes found matching your criteria. Try expanding the search window or lowering the magnitude.")
+