diff options
Diffstat (limited to '.idea/gtfs-book/ch-03-stops.md')
| -rw-r--r-- | .idea/gtfs-book/ch-03-stops.md | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/.idea/gtfs-book/ch-03-stops.md b/.idea/gtfs-book/ch-03-stops.md new file mode 100644 index 0000000..cd8dedb --- /dev/null +++ b/.idea/gtfs-book/ch-03-stops.md @@ -0,0 +1,117 @@ +## 3. Stops & Stations (stops.txt) + +*This file is ***required*** to be included in GTFS feeds.* + +The individual locations where vehicles pick up or drop off passengers +are represented by `stops.txt`. Records in this file are referenced in +`stop_times.txt`. A record in this file can be either a stop or a +station. A station has one or more child stops, as indicated using the +`parent_station` value. Entries that are marked as stations may not +appear in `stop_times.txt`. + +| Field | Required? | Description | +| :----- | :-------- | :---------- | +| `stop_id` | Required | An ID to uniquely identify a stop or station. | +| `stop_code` | Optional | A number or short string used to identify a stop to passengers. This is typically displayed at the physical stop or on printed schedules. | +| `stop_name` | Required | The name of the stop as passengers know it by. | +| `stop_desc` | Optional | A description of the stop. If provided, this should provide additional information to the `stop_name` value. | +| `stop_lat` | Required | The latitude of the stop (a number in the range of `-90` to `90`). | +| `stop_lon` | Required | The longitude of the stop (a number in the range of `-180` to `180`). | +| `zone_id` | Optional | This is an identifier used to calculate fares. A single zone ID may appear in multiple stops, but is ignored if the stop is marked as a station. | +| `stop_url` | Optional | A URL that provides information about this stop. It should be specific to this stop and not simply link to the agency's web site. | +| `location_type` | Optional | Indicates if a record is a stop or station. `0` or blank means a stop, `1` means a station. | +| `parent_station` | Optional | If a record is marked as a stop and has a parent station, this contains the ID of the parent (the parent must have a `location_type` of `1`). | +| `stop_timezone` | Optional | If a stop is located in a different time zone to the one specified in `agency.txt`, then it can be overridden here. | +| `wheelchair_boarding` | Optional | A value of `1` indicates it is possible for passengers in wheelchairs to board or alight. A value of `2` means the stop is not wheelchair accessible, while `0` or an empty value means no information is available. If the stop has a parent station, then 0 or an empty value means to inherit from its parent. | + +### Sample Data + +The following extract is taken from the TriMet GTFS feed +(<https://openmobilitydata.org/p/trimet>). + +| `stop_id` | `stop_code` | `stop_name` | `stop_lat` | `stop_lon` | `stop_url` | +| :-------- | :----------- | :------------------ | :---------- | :------------ | :---------------------------------------------------| +| `2` | `2` | `A Ave & Chandler` | `45.420595` | `-122.675676` |` <http://trimet.org/arrivals/tracker?locationID=2>` | +| `3` | `3` | `A Ave & Second St` | `45.419386` | `-122.665341` |` <http://trimet.org/arrivals/tracker?locationID=3>` | +| `4` | `4` | `A Ave & 10th St` | `45.420703` | `-122.675152` |` <http://trimet.org/arrivals/tracker?locationID=4>` | +| `6` | `6` | `A Ave & 8th St` | `45.420217` | `-122.67307` |` <http://trimet.org/arrivals/tracker?locationID=6>` | + +The following diagram shows how these points look if you plot them onto +a map. + + + +In this extract, TriMet use the same value for stop IDs and stop codes. +This is useful, because it means the stop IDs are stable (that is, they +do not change between feed versions). This means that if you want to +save a particular stop (for instance, if a user wants to save a +"favorite stop") you can trust that saving the ID will get the job done. + +**Note:** This is not always the case though, which means you may have +to save additional information if you want to save a stop. For instance, +you may need to save the coordinates or the list of routes a stop serves +so you can find it again if the stop ID has changed in a future version +of the feed. + +### Stops & Stations + +Specifying an entry in this file as a *station* is typically used when +there are many stops located within a single physical entity, such as a +train station or bus depot. While many feeds do not offer this +information, some large train stations may have up to 20 or 30 +platforms. + +Knowing the platform for a specific trip is extremely useful, but if a +passenger wants to select a starting point for their trip, showing them +a list of platforms may be confusing. + +Passenger: + +**"I want to travel from *Central Station* to *Airport Station*."** + +Web site / App: + +**"Board at *Central Station platform 5*, disembark at *Airport Station platform 1*."** + +In this example, the passenger selects the parent station, but they are +presented with the specific stop so they know exactly where within the +station they need to embark or disembark. + +### Wheelchair Accessibility + +If you are showing wheelchair accessibility information, it is important +to differentiate between "no access" and "no information", as knowing a +stop is not accessible is as important as knowing it is. + +If a stop is marked as being wheelchair accessible, you must check that +trips that visit the stop are also accessible (using the +`wheelchair_accessible` field in `trips.txt`). If the value in +`trips.txt` is blank, `0` or `1` then it is safe to assume the +trip can be accessed. If the stop is accessible and the trip is not, +then passengers in wheelchairs cannot use the trip. + +### Stop Features + +One of the proposed changes to GTFS is the addition of a file called +`stop_features.txt`. This is used to define characteristics about +stops. The great thing about this file is that it allows you to indicate +to users when a stop has a ticket machine, bike storage, lighting, or an +electronic display with real-time information. + +TriMet is one of the few agencies including this file. The following is +a sample of this file. + +| `stop_id` | `feature_type` | +| :-------- | :------------- | +| `61` | `4110` | +| `61` | `2310` | +| `61` | `5200` | + +This data indicate that stop `61` (NE Alberta & 24th) has a *Printed +Schedule Display* (`4110`), a *Bike Rack* (`2310`) and a *Street +Light* (`5200`). + +For more information about this proposal and a list of values and their +meanings, refer to +<https://sites.google.com/site/gtfschanges/proposals/stop-amenity>. + |