get_calendar_overlap: Get calendar overlap

In gtfstools: General Transit Feed Specification (GTFS) Editing and Analysing Tools

Get calendar overlap

Description

Returns the periods in which all the given GTFS feeds have service, or the number of trips each feed runs on each of its service days. Either result can also be plotted. Useful to pick a date on which several feeds can be analysed together (e.g. when routing on the networks of different agencies).

Usage

get_calendar_overlap(gtfs, resolution = "daily", plot = FALSE)

Arguments

gtfs	Either a character vector with the paths to GTFS .zip files or a list of GTFS objects, as created by read_gtfs() (a single GTFS object must be wrapped in a list).
resolution	A string. "daily" (the default) returns the number of trips of each feed on each of its service days, and "periods" the periods in which all feeds have service.
plot	A logical. Whether to return a plot of the result instead of the result itself (requires the {ggplot2} package). Defaults to FALSE.

Value

If plot = FALSE and resolution = "periods", a data.table with one row per period of consecutive days on which all feeds have service, and the columns start_date, end_date (both included in the period) and n_days. It has no rows if there is no such day.

If plot = FALSE and resolution = "daily", a data.table with one row per feed and service day, and the columns feed, date, n_trips (the number of trips that run on the day) and overlap (whether all feeds have service on the day).

If plot = TRUE, a ggplot object with dates on the x axis and one row per feed (top to bottom in the given order). With resolution = "periods", it shows a bar spanning each feed's service days. With resolution = "daily", it shows a box plot of when each feed's trips run: the box spans the days by which a quarter and three quarters of its trips have run, with a line on the day by which half have, and the whiskers reach its first and last service days. In both, the overlap periods are shaded.

Details

A feed has service on a day if at least one of its services runs on it, according to calendar and calendar_dates (either may be missing). A service both added and removed on a day in calendar_dates runs on it. If trips has a service_id field, services not used by any trip are ignored. feed_info dates are not used. A warning is raised for feeds without any service day, and a message when two or more feeds have no day with service in all of them.

In n_trips, a trip listed in frequencies counts once per departure, as in frequencies_to_stop_times() with strategy = "exact", except that the departures of overlapping entries of the same trip are added up (identical entries count once). A trip with an invalid frequencies entry counts once, with a warning. Departures after midnight (times past "24:00:00") count on the previous day. Without a trips table with a service_id field, n_trips is NA and the daily plot shows no box for the feed.

Feeds are named after their file names (without the extension) or list names; unnamed feeds are named "feed_1", "feed_2", etc., and duplicated names are made unique. Overlap periods are shaded only when two or more feeds are given.

See Also

merge_gtfs(), filter_by_service_id()

Examples

spo_path <- system.file("extdata/spo_gtfs.zip", package = "gtfstools")
poa_path <- system.file("extdata/poa_gtfs.zip", package = "gtfstools")

# feeds may be given as paths to their .zip files
daily_trips <- get_calendar_overlap(c(spo_path, poa_path))
head(daily_trips)

# or as a list of GTFS objects, whose names are used as feed names
feeds <- list(spo = read_gtfs(spo_path), poa = read_gtfs(poa_path))
get_calendar_overlap(feeds, resolution = "periods")

if (requireNamespace("ggplot2", quietly = TRUE)) {
  get_calendar_overlap(feeds, plot = TRUE)
}

gtfstools documentation built on Oct. 28, 2026, 5:13 p.m.