Returns the length of each specified trip_id, based either on the shapes
or the stop_times file (or both).
get_trip_length(gtfs, trip_id = NULL, file = NULL, unit = "km")A GTFS object, as created by read_gtfs().
A character vector including the trip_ids to have their
length calculated If NULL (the default), the function calculates the
length of each trip_id in the GTFS.
A character vector specifying the file from which lengths should
be calculated (either one of or both shapes and stop_times). If NULL
(the default), the function attempts to calculate the lengths from both
files, but only raises an error if none of the files exist.
A string representing the unit in which lengths are desired.
Either "km" (the default) or "m".
A data.table containing the length of each specified trip.
Please check get_trip_geometry() documentation to understand how geometry
generation, and consequently length calculation, differs depending on the
chosen file.
data_path <- system.file("extdata/spo_gtfs.zip", package = "gtfstools")
gtfs <- read_gtfs(data_path)
trip_length <- get_trip_length(gtfs)
head(trip_length)
#> trip_id length origin_file
#> <char> <num> <char>
#> 1: CPTM L07-0 60.71894 shapes
#> 2: CPTM L07-1 60.71894 shapes
#> 3: CPTM L08-0 41.79037 shapes
#> 4: CPTM L08-1 41.79037 shapes
#> 5: CPTM L09-0 31.88906 shapes
#> 6: CPTM L09-1 31.88906 shapes
# the above is identical to
trip_length <- get_trip_length(gtfs, file = c("shapes", "stop_times"))
head(trip_length)
#> trip_id length origin_file
#> <char> <num> <char>
#> 1: CPTM L07-0 60.71894 shapes
#> 2: CPTM L07-1 60.71894 shapes
#> 3: CPTM L08-0 41.79037 shapes
#> 4: CPTM L08-1 41.79037 shapes
#> 5: CPTM L09-0 31.88906 shapes
#> 6: CPTM L09-1 31.88906 shapes
trip_ids <- c("CPTM L07-0", "2002-10-0")
trip_length <- get_trip_length(gtfs, trip_id = trip_ids)
trip_length
#> trip_id length origin_file
#> <char> <num> <char>
#> 1: CPTM L07-0 60.718942 shapes
#> 2: 2002-10-0 7.162009 shapes
#> 3: CPTM L07-0 55.176541 stop_times
#> 4: 2002-10-0 5.247691 stop_times