get_trip_speed: Get trip speed

Description

Returns the speed of each specified trip_id, based on the geometry created from either the shapes or the stop_times file (or both).

Usage

get_trip_speed(
  gtfs,
  trip_id = NULL,
  file = "shapes",
  unit = "km/h",
  sort_sequence = FALSE
)

Value

A data.table containing the duration of each specified trip and the file from which geometries were generated.

Arguments

gtfs: A GTFS object, as created by read_gtfs().
trip_id: A character vector including the trip_ids to have their speeds calculated. If NULL (the default), the function calculates the speed of every trip_id in the GTFS.
file: The file from which geometries should be generated, either shapes or stop_times (geometries are used to calculate the length of a trip). Defaults to shapes.
unit: A string representing the unit in which the speeds are desired. Either "km/h" (the default) or "m/s".
sort_sequence: Ultimately passed to get_trip_length(), a logical specifying whether to sort shapes and timetables by shape_pt_sequence and stop_sequence, respectively. Speeds calculated from trip trajectories generated with unordered sequences do not correctly depict the actual trip speeds. Defaults to FALSE, otherwise spec-compliant feeds, in which shape/timetables points are already ordered by shape_pt_sequence/stop_sequence, would be penalized through longer processing times.

Details

Please check get_trip_geometry() documentation to understand how geometry generation differs depending on the chosen file.

Examples

Run this code

# \dontshow{
  old_dt_threads <- data.table::setDTthreads(1)
  on.exit(data.table::setDTthreads(old_dt_threads), add = TRUE)
# }
data_path <- system.file("extdata/spo_gtfs.zip", package = "gtfstools")

gtfs <- read_gtfs(data_path)

trip_speed <- get_trip_speed(gtfs)
head(trip_speed)

trip_ids <- c("CPTM L07-0", "2002-10-0")
trip_speed <- get_trip_speed(gtfs, trip_ids)
trip_speed

trip_speed <- get_trip_speed(
  gtfs,
  trip_ids,
  file = c("shapes", "stop_times")
)
trip_speed

trip_speed <- get_trip_speed(gtfs, trip_ids, unit = "m/s")
trip_speed