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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")

You can install latest stable version of gtfsrouter from CRAN with:

install.packages("gtfsrouter") # current CRAN version

Alternatively, current development versions can be installed using any of the following options:

# install.packages("remotes")
remotes::install_git("https://git.sr.ht/~mpadge/gtfsrouter")
remotes::install_bitbucket("atfutures/gtfsrouter")
remotes::install_gitlab("atfutures1/gtfsrouter")
remotes::install_github("ATFutures/gtfsrouter")

To load the package and check the version:

library(gtfsrouter)
packageVersion("gtfsrouter")

## [1] '0.0.1.31'

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/RtmpctrGeB/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

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.

Additional Functionality

There are many ways to construct GTFS feeds. For background information, see gtfs.org, and particularly their GTFS Examples.

Feeds may include a “frequencies.txt” table which defines “service periods”, and overrides any schedule information during the specified times. The gtfsrouter package includes a function, frequencies_to_stop_times(), to convert “frequencies.txt” tables to equivalent “stop_times.txt” entries, to enable the feed to be used for routine.

Feeds may also omit a “transfers.txt” table which otherwise defines transfer abilities and times between different services. Feeds without this table can generally not be used for routing, and they exclude the possibility of transferring between multiple services. The gtfsrouter package also includes a function, gtfs_transfer_table(), which can calculate a transfer table for a given feed, with transfer times calculated either using straight-line distances (the default), or using more realistic times routed through the underlying street network.

Contributors

This project uses the allcontributor package following the all-contributors specification. Contributions of any kind are welcome!

Code

Issue Authors