gtfs_traveltimes {gtfsrouter}

gtfs_traveltimes

Description

Travel times from a nominated station departing at a nominated time to every other reachable station in a system.

Usage

gtfs_traveltimes(
  gtfs,
  from,
  start_time_limits,
  day = NULL,
  from_is_id = FALSE,
  grep_fixed = TRUE,
  route_pattern = NULL,
  minimise_transfers = FALSE,
  max_traveltime = 60 * 60,
  quiet = FALSE
)

Arguments

gtfs

A set of GTFS data returned from extract_gtfs or, for more efficient queries, pre-processed with gtfs_timetable.

from

Name, ID, or approximate (lon, lat) coordinates of start station (as stop_name or stop_id entry in the stops table, or a vector of two numeric values).

start_time_limits

A vector of two integer values denoting the earliest and latest departure times in seconds for the traveltime values.

day

Day of the week on which to calculate route, either as an unambiguous string (so "tu" and "th" for Tuesday and Thursday), or a number between 1 = Sunday and 7 = Saturday. If not given, the current day will be used. (Not used if gtfs has already been prepared with gtfs_timetable.)

from_is_id

Set to TRUE to enable from parameter to specify entry in stop_id rather than stop_name column of the stops table (same as from_to_are_ids parameter of gtfs_route).

grep_fixed

If FALSE, match station names (when passed as character string) with grep(..., fixed = FALSE), to allow use of grep expressions. This is useful to refine matches in cases where desired stations may match multiple entries.

route_pattern

Using only those routes matching given pattern, for example, "^U" for routes starting with "U" (as commonly used for underground or subway routes. To negate the route_pattern – that is, to include all routes except those matching the pattern – prepend the value with "!"; for example "!^U" will include all services except those starting with "U". (This parameter is not used at all if gtfs has already been prepared with gtfs_timetable.)

minimise_transfers

If TRUE, isochrones are calculated with minimal-transfer connections to each end point, even if those connections are slower than alternative connections with transfers.

max_traveltime

The maximal traveltime to search for, specified in seconds (with default of 1 hour). See note for details.

quiet

Set to TRUE to suppress screen messages (currently just regarding timetable construction).

Value

A data.frame of travel times and required numbers of transfers to all stations reachable from the given from station. Additional columns include "start_time" of connection, and information on destination stops including "id" numbers, names, and geographical coordinates.

Note

Higher values of max_traveltime will return traveltimes for greater numbers of stations, but may lead to considerably longer calculation times. For repeated usage, it is recommended to first establish a value sufficient to reach all or most stations desired for a particular query, rather than set max_traveltime to an arbitrarily high value.

See Also

Other main: gtfs_route_headway(), gtfs_route()

Examples

# Examples must be run on single thread only:
nthr <- data.table::setDTthreads (1)

berlin_gtfs_to_zip ()
f <- file.path (tempdir (), "vbb.zip")
g <- extract_gtfs (f)
g <- gtfs_timetable (g)
from <- "Alexanderplatz"
start_times <- 12 * 3600 + c (0, 60) * 60 # 8:00-9:00
res <- gtfs_traveltimes (g, from, start_times)

data.table::setDTthreads (nthr)