hansmib / gtfs-router

Routing and analysis engine for GTFS (General Transit Feed Specification) data

GTFS Router

R package for routing with GTFS (General Transit Feed Specification) data. See the website for full details.

Installation

To install:

remotes::install_github("atfutures/gtfs-router")

To load the package and check the version:

library(gtfsrouter)
packageVersion("gtfsrouter")

## [1] '0.0.1'

Main functions

The main functions can be demonstrated with sample data included with the package from Berlin (the Verkehrverbund Berlin Brandenburg, or VBB). GTFS data are always stored as .zip files, and these sample data can be written to local storage with the function berlin_gtfs_to_zip().

berlin_gtfs_to_zip()
tempfiles <- list.files (tempdir (), full.names = TRUE)
filename <- tempfiles [grep ("vbb.zip", tempfiles)]
filename

## [1] "/tmp/Rtmpz6vX0h/vbb.zip"

For normal package use, filename will specify the name of the local GTFS data stored as a single .zip file.

gtfs_route

Given the name of a GTFS .zip file, filename, routing is as simple as the following code:

gtfs <- extract_gtfs (filename)
gtfs <- gtfs_timetable (gtfs) # A pre-processing step to speed up queries
gtfs_route (gtfs,
            from = "Schonlein",
            to = "Berlin Hauptbahnhof",
            start_time = 12 * 3600 + 120) # 12:02 in seconds

route_name	trip_name	stop_name	arrival_time	departure_time
U8	U Paracelsus-Bad	U Schonleinstr. (Berlin)	12:04:00	12:04:00
U8	U Paracelsus-Bad	U Kottbusser Tor (Berlin)	12:06:00	12:06:00
U8	U Paracelsus-Bad	U Moritzplatz (Berlin)	12:08:00	12:08:00
U8	U Paracelsus-Bad	U Heinrich-Heine-Str. (Berlin)	12:09:30	12:09:30
U8	U Paracelsus-Bad	S+U Jannowitzbrucke (Berlin)	12:10:30	12:10:30
S5	S Westkreuz	S+U Jannowitzbrucke (Berlin)	12:15:24	12:15:54
S5	S Westkreuz	S+U Alexanderplatz Bhf (Berlin)	12:17:24	12:18:12
S5	S Westkreuz	S Hackescher Markt (Berlin)	12:19:24	12:19:54
S5	S Westkreuz	S+U Friedrichstr. Bhf (Berlin)	12:21:24	12:22:12
S5	S Westkreuz	S+U Berlin Hauptbahnhof	12:24:06	12:24:42

gtfs_isochrone

Isochrones from a nominated station - lines delineating the range reachable within a given time - can be extracted with the gtfs_isochrone() function, which returns a list of all stations reachable within the specified time period from the nominated station.

gtfs <- extract_gtfs (filename)
gtfs <- gtfs_timetable (gtfs) # A pre-processing step to speed up queries
x <- gtfs_isochrone (gtfs,
                     from = "Schonlein",
                     start_time = 12 * 3600 + 120,
                     end_time = 12 * 3600 + 720) # 10 minutes later

The function returns an object of class gtfs_isochrone containing sf-formatted sets of start and end points, along with all intermediate (“mid”) points, and routes. An additional item contains the non-convex (alpha) hull enclosing the routed points. This requires the packages geodist, sf, alphahull, and mapview to be installed. Isochrone objects have their own plot method:

plot (x)

The isochrone hull also quantifies its total area and width-to-length ratio.

GTFS Structure

For background information, see gtfs.org, and particularly their GTFS Examples. The VBB is strictly schedule-only, so has no "frequencies.txt" file (this file defines “service periods”, and overrides any schedule information during the specified times).