convert_shapes_to_sf    Convert 'shapes' table to simple feature object
convert_stops_to_sf     Convert 'stops' table to simple feature object
convert_time_to_seconds
                        Convert time fields to seconds after midnight
download_validator      Download MobilityData's GTFS validator
filter_by_agency_id     Filter GTFS object by 'agency_id'
filter_by_route_id      Filter GTFS object by 'route_id'
filter_by_route_type    Filter GTFS object by 'route_type' (transport
                        mode)
filter_by_service_id    Filter GTFS object by 'service_id'
filter_by_sf            Filter a GTFS object using a simple features
                        object
filter_by_shape_id      Filter GTFS object by 'shape_id'
filter_by_stop_id       Filter GTFS object by 'stop_id'
filter_by_time_of_day   Filter GTFS object by time of day
filter_by_trip_id       Filter GTFS object by 'trip_id'
filter_by_weekday       Filter GTFS object by weekday
frequencies_to_stop_times
                        Convert frequencies to stop times
get_children_stops      Get children stops recursively
get_parent_station      Get parent stations recursively
get_stop_times_patterns
                        Get stop times patterns
get_trip_duration       Get trip duration
get_trip_geometry       Get trip geometry
get_trip_length         Get trip length
get_trip_segment_duration
                        Get trip segments' duration
get_trip_speed          Get trip speed
merge_gtfs              Merge GTFS files
read_gtfs               Read GTFS files
remove_duplicates       Remove duplicated entries
set_trip_speed          Set trip average speed
validate_gtfs           Validate GTFS feed
write_gtfs              Write GTFS files
