ratp-gtfs-to-json

Create a JSON graph from RATP open data (http://data.ratp.fr/fr/les-donnees/fiche-de-jeu-de-donnees/dataset/offre-transport-de-la-ratp-format-gtfs.html)

This is part of fxos-metrobusparis

Data Overview

The goal of these scripts is to parse the GTFS files to create a Graph usable to find shortest paths

The GTFS structure is :

Line X directory

routes.txt	trips.txt	stop_times.txt	stops.txt
route_id	route_id	stop_id	stop_id
trip_id	trip_id	trip_id	stop_name
type		arrival_time
line (directory)

And the output is :

{
    <stop_id>: {
        name: <name>,
        loc: {
            lat: <latitude>,
            lon: <longitude>
        }
        zip: <zipcode>,
        edges: [
            {
                "dest": <dest_stop_id>,
                "dur": <edge_duration>,
                "type": <edge_type>,
                "open": <hour_of_opening>,
                "close": <hour_of_closing>,
                "line": <line_number>,
                "dir": <line_direction>,
                "freq": <average_frequency>
            }
        ]
    }
}

You can see the full RATP GTFS description in the PDF file in the page linked above (direct link: http://data.ratp.fr/?eID=ics_od_datastoredownload&file=88)

Scripts overview

create_raw_edges.c

Crunch all the stops informations from stop_times.txt (> 600MB, millions of lines) and output edges with average duration, frequency and open hours

create_graph.rb

Create graph nodes by browsing GTFS lines directories to get line informations (line name, directions...) and parse the output of create_raw_edges.c above to create final graph

The stops (stations) with identical names are merged to reduce graph size because in the original GTFS files there is one stop_id per line per direction.

See comments in the scripts for further explanations.

Usage

gcc create_raw_edges.c lib/r_hashtable.c lib/r_linkedlist.c -I lib/ -o create_raw_edges create_raw_edges <RATP_GTFS_FULL directory> > edges.txt create_graph.rb <RATP_GTFS_LINES directory> <RATP_GTFS_FULL directory> <edges.txt> <output.json>

Licence

(c) 2013 Romain BEAUDON This code may be freely distributed under the terms of the GPL3 Licence