R/gtfs_subset.R

In mem48/UK2GTFS: Converts UK transport timetable datasets to GTFS format

gtfs_subset <- function(gtfs, bounds) {
  stops <- gtfs$stops
  stop_times <- gtfs$stop_times

  bbox <- sf::st_bbox(bounds)

  stops_inc <- stops[!is.na(stops$stop_lon), ]
  stops_inc$stop_lon <- as.numeric(stops_inc$stop_lon)
  stops_inc$stop_lat <- as.numeric(stops_inc$stop_lat)

  stops_inc <- stops_inc[stops_inc$stop_lon > bbox[1], ]
  stops_inc <- stops_inc[stops_inc$stop_lon < bbox[3], ]
  stops_inc <- stops_inc[stops_inc$stop_lat > bbox[2], ]
  stops_inc <- stops_inc[stops_inc$stop_lat < bbox[4], ]
  # stops2 <- sf::st_as_sf(stops_inc, coords = c("stop_lon","stop_lat"), crs = 4326)
  # qtm(stops2)

  tripids <- unique(stop_times$trip_id[stop_times$stop_id %in% stops_inc$stop_id])
  gtfs <- gtfs_split(gtfs_merged, tripids)
  gtfs <- gtfs$true
  return(gtfs)
}