filter_by_date: Filter GTFS object by date

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

Filter GTFS object by date

Description

Filters a GTFS object by the services that run on the given dates, keeping (or dropping) the relevant entries in each file.

Usage

filter_by_date(gtfs, date, keep = TRUE)

Arguments

gtfs	A GTFS object, as created by read_gtfs().
date	A Date vector (including IDate) or a character vector of dates in the "YYYYMMDD" or "YYYY-MM-DD" formats. The dates used to filter the data.
keep	A logical. Whether the entries related to the services that run on the specified dates should be kept or dropped (defaults to TRUE, which keeps the entries).

Value

The GTFS object passed to the gtfs parameter, after the filtering process.

Details

The services that run on at least one of the given dates are kept (or dropped) as a whole: their calendar and calendar_dates entries are not trimmed to the given dates, so they may still run on other dates.

A service runs on a date if its calendar entry spans the date and flags its weekday, unless the date is removed from it in calendar_dates (exception_type 2), or if the date is added to it in calendar_dates (exception_type 1). An addition wins over a removal on the same date. Either table may be missing. If both are missing, the GTFS object is returned unchanged, with a warning.

See Also

filter_by_weekday(), get_calendar_overlap()

Other filtering functions: filter_by_agency_id(), filter_by_period(), filter_by_route_id(), filter_by_route_type(), filter_by_service_id(), filter_by_shape_id(), filter_by_spatial_extent(), filter_by_stop_id(), filter_by_time_of_day(), filter_by_trip_id(), filter_by_weekday()

Examples

data_path <- system.file("extdata/ggl_gtfs.zip", package = "gtfstools")
gtfs <- read_gtfs(data_path)

# on 2006-07-03 (a monday) the weekday service "WD" is replaced by the
# weekend service "WE", according to the calendar_dates table
gtfs$calendar_dates

smaller_gtfs <- filter_by_date(gtfs, "2006-07-03")
smaller_gtfs$calendar

# dates may also be given as Date objects. drops the services that run on
# 2006-07-05 (a wednesday)
smaller_gtfs <- filter_by_date(gtfs, as.Date("2006-07-05"), keep = FALSE)
smaller_gtfs$calendar

# a vector of dates keeps the services that run on at least one of them
week <- seq(as.Date("2006-07-01"), as.Date("2006-07-07"), by = "day")
smaller_gtfs <- filter_by_date(gtfs, week)
smaller_gtfs$calendar

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