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Extend prioritization with GTFS-RT based speed metrics

Source: R/rt_extend_prioritization.R
rt_extend_prioritization.Rd

This function extends lane segment indicators for prioritization with speed metrics produced with GTFS-RT data.

Usage

rt_extend_prioritization(
  lane_prioritization,
  rt_collection,
  rt_current_status = c("IN_TRANSIT_TO"),
  lane_buffer = 15,
  metric_crs = 3857
)

Arguments

lane_prioritization

sf data.frame. Result of GTFShift::prioritize_lanes()

rt_collection

sf data.frame. GTFS-RT data collection. Must include speed column.

rt_current_status

Character vector (Default c("IN_TRANSIT_TO")). If the current_status column is present in the rt_collection data, only points with current_status in this vector are considered.

lane_buffer

numeric (Default 15). Buffer distance (in meters) to create around lane segments to capture nearby GTFS-RT points.

metric_crs

Integer or character (Default 3857). Projected CRS used to apply lane buffer distances in meters.

Value

The lane_prioritization sf data.frame, extended with the following columns:

speed_avg

The average speed of the vehicles on the way.

speed_median

The median speed of the vehicles on the way.

speed_p25

The 25th percentile speed of the vehicles on the way.

speed_p75

The 75th percentile speed of the vehicles on the way.

speed_count

The number of speed observations on the way.

Details

Extends the lane_prioritization data with speed metrics calculated from the GTFS-RT data points that fall within a buffer around each lane segment.

If GTFS-RT data does not provide speed information, it can be inferred from the progression of position updates through time using GTFShift::rt_average_speed().

Refer to GTFShift::rt_collect_json() or GTFShift::rt_collect_protobuf() for details on GTFS-RT data collection.

Examples

if (FALSE) { # \dontrun{
rt_collect_file <- "gtfs_rt_data.csv"
GTFShift::rt_collect_json("https://api.example.com/gtfs-rt", rt_collect_file)
lane_prioritization <- GTFShift::prioritize_lanes(gtfs, osm_query)

rt_collection <- read.csv(rt_collect_file) |> sf::st_as_sf(coords = c("longitude", "latitude"), crs = 4326)
lane_prioritization_extended <- GTFShift::rt_extend_prioritization(
  lane_prioritization = lane_prioritization,
  rt_collection = rt_collection
)
} # }