Trim a GTFS file between two dates

Trim a GTFS file between two dates

Usage

gtfs_trim_dates(
  gtfs,
  startdate = lubridate::ymd("2020-03-01"),
  enddate = lubridate::ymd("2020-04-30")
)

Arguments

gtfs

GTFS object from gtfs_read()

startdate

Start date

enddate

End date

Value

a gtfs object trimmed to services running between the two dates

Details

The GTFS specification allows a `service_id` to be defined in `calendar_dates.txt` alone, with no row in `calendar.txt`; the service then runs on exactly the dates listed with `exception_type = 1`. Such services are kept if any of those dates falls inside the window. The DfT's Bus Open Data Service GTFS uses them heavily (for example for school-holiday timetables), so dropping them silently removes real service.