1 files changed, 92 insertions, 0 deletions
diff --git a/trip_geo.py b/trip_geo.py
new file mode 100644
index 0000000..c6d88db
--- /dev/null
+++ b/trip_geo.py
@@ -0,0 +1,92 @@
+# /// script
+# requires-python = ">=3.13"
+# dependencies = [
+#     "pandas",
+# ]
+# ///
+
+import argparse
+import os
+import pandas as pd
+
+if __name__ != "__main__":
+    raise RuntimeError("This script is meant to be run as a standalone program, not imported as a module.")
+
+parser = argparse.ArgumentParser(description="Extract GeoJSON from GTFS feed and save to file")
+parser.add_argument(
+    "gtfs_path",
+    type=str,
+    help="Path to the GTFS feed directory"
+)
+
+parser.add_argument(
+    "trip_id",
+    type=str,
+    help="ID of the trip to extract from the GTFS feed"
+)
+
+args = parser.parse_args()
+
+gtfs_path = args.gtfs_path
+trip_id = args.trip_id
+
+# Load trips.txt, stop_times.txt, stops.txt and shapes.txt
+
+trips_df = pd.read_csv(os.path.join(gtfs_path, "trips.txt"))
+stop_times_df = pd.read_csv(os.path.join(gtfs_path, "stop_times.txt"))
+stops_df = pd.read_csv(os.path.join(gtfs_path, "stops.txt"))
+shapes_df = pd.read_csv(os.path.join(gtfs_path, "shapes.txt"))
+
+# Find the shape_id for the given trip_id
+trip_row = trips_df[trips_df["trip_id"] == trip_id]
+if trip_row.empty:
+    raise ValueError(f"Trip ID {trip_id} not found in trips.txt")
+
+shape_id = trip_row.iloc[0]["shape_id"]
+if pd.isna(shape_id):
+    raise ValueError(f"No shape_id found for Trip ID {trip_id}")
+
+# Extract the shape points for the shape_id
+shape_points = shapes_df[shapes_df["shape_id"] == shape_id].sort_values(by="shape_pt_sequence")
+
+# Find the stop sequence for the trip_id and get the stop coordinates
+stop_times = stop_times_df[stop_times_df["trip_id"] == trip_id].sort_values(by="stop_sequence")
+stop_ids = stop_times["stop_id"].tolist()
+stops = stops_df[stops_df["stop_id"].isin(stop_ids)]
+
+# Convert shape points to GeoJSON LineString format
+geojson = {
+    "type": "FeatureCollection",
+    "features": [
+        {
+            "type": "Feature",
+            "geometry": {
+                "type": "LineString",
+                "coordinates": shape_points.apply(lambda row: [row["shape_pt_lon"], row["shape_pt_lat"]], axis=1).tolist()
+            },
+            "properties": {
+                "headsign": trip_row.iloc[0]["trip_headsign"],
+                "shape_id": shape_id
+            }
+        },
+        *[{
+            "type": "Feature",
+            "geometry": {
+                "type": "Point",
+                "coordinates": [x.stop_lon, x.stop_lat]
+            },
+            "properties": {
+                "name": x.stop_name,
+                "stop_id": x.stop_id,
+                "code": x.stop_code
+            }
+        } for _, x in stops.iterrows()]
+    ]
+}
+
+# Save GeoJSON to file
+output_file = f"{trip_id}_shape.geojson"
+
+with open(output_file, "w") as f:
+    import json
+    json.dump(geojson, f, indent=2)