adjust_arrival_departure
                        Adjust the arrival and departure times of a
                        GTFS data
adjust_speed            Adjust the speeds of a gps-like table created
                        with 'gtfs2gps'
append_height           Add a column with height to GPS data
cpp_snap_points_nearest1
                        Snap points to the closest points from another
                        set
cpp_snap_points_nearest2
                        Snap points to the closest points from another
                        set
filter_by_agency_id     Filter GTFS data by agency ids
filter_by_day           Filter GTFS trips operating on given days
filter_by_route_id      Filter GTFS data by route ids
filter_by_route_type    Filter GTFS data by transport mode (route type)
filter_by_shape_id      Filter GTFS data by shape ids
filter_day_period       Filter GTFS data within a period of the day
filter_single_trip      Filter GTFS trips in order to have one trip per
                        shape_id
filter_valid_stop_times
                        Filter GTFS data using valid stop times
filter_week_days        Filter GTFS trips operating on week days
gps_as_sflinestring     Converts a GPS-like data.table to a LineString
                        Simple Feature (sf) object
gps_as_sfpoints         Convert GPS-like data.table to a Simple Feature
                        points object
gtfs2gps                Convert GTFS to GPS-like data given a spatial
                        resolution
gtfs_shapes_as_sf       Convert GTFS shapes to simple feature object
gtfs_stops_as_sf        Convert GTFS stops to simple feature object
merge_gtfs_feeds        Merge multiple GTFS feeds into a single one
read_gtfs               Read GTFS data into a list of data.tables
remove_by_route_id      Remove GTFS data by route ids
remove_invalid          Remove invalid objects from GTFS data
simplify_shapes         Simplify shapes of a GTFS file
test_gtfs_freq          Test whether a GTFS feed is frequency based
write_gtfs              Write GTFS data into a zip file
