public transport stop_area relations: have you implemented for routing or another purpose?

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public transport stop_area relations: have you implemented for routing or another purpose?

Joseph Eisenberg
I'm trying to find out if the type=public_transport +
public_transport=stop_area relation or *=stop_area_group relation is
used by any developer or database user.

These relations are supposed to group together features like all the
platforms in a bus station or train station. However, it seems like
these relations may not be necessary or useful for routing
applications.

Has anyone looked into them or know of any current use cases?

Joseph

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Re: public transport stop_area relations: have you implemented for routing or another purpose?

Jo-2
First off, I'm not mapping stop_area relations very often, only in case of ambiguity. A stop near to a side street, but the bus passes on the main street, or in bus stations where everything is very near to the other objects.

JOSM's PT_Assistant plugin uses them to figure out which stop_position + way adjacent to a highway=bus_stop node, if they are available. Usually it's possible to determine it geographically. It also only works if the stop_area relation contains pairs of stop_position / bus_stop nodes. If someone simply throws all stop_position nodes, bus_stop nodes and platform ways into them for stops on both sides of a street, or all stops in a bus station, they are useless for that purpose.

Since, at that level, I'm using them to pair stop objects, I also have a hierarchy of stop_area relations in some places. (bus stations adjacent to railway or metro stations). At some point I was using stop_area_group for that, but JOSM doesn't recognise that.

I don't know of any external app that uses them.

Polyglot

On Thu, Aug 1, 2019 at 9:13 AM Joseph Eisenberg <[hidden email]> wrote:
I'm trying to find out if the type=public_transport +
public_transport=stop_area relation or *=stop_area_group relation is
used by any developer or database user.

These relations are supposed to group together features like all the
platforms in a bus station or train station. However, it seems like
these relations may not be necessary or useful for routing
applications.

Has anyone looked into them or know of any current use cases?

Joseph

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[hidden email]
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Re: public transport stop_area relations: have you implemented for routing or another purpose?

Andrew Byrd
In reply to this post by Joseph Eisenberg
Hello,

I work on public transport journey planning software. We use OSM data heavily, but primarily for the parts of journeys outside public transportation: the first- or last-mile or transfer segments. In my experience we rarely use OSM data directly for the transit part of routing. We use data loaded from GTFS or Netex feeds, which are provided by the public transportation operators or regional authorities. Public transport entities or tags from OSM are generally used as a sanity check or backup source of information, for example to determine from which road it is easiest to reach a stop, when that stop is physically located halfway between two candidate roads.

These data sources do have a concept of stop hierarchies. GTFS groups stops into stations, and Netex allows more complex hierarchies. If data of this kind are imported into OSM, or if the data in OSM are expected to resemble the conceptual model used in exchanging public transport data, then I'd expect these groupings to be present. I can confirm that the groupings are meaningful and useful in routing applications, both when finding paths and when presenting those paths to the end user.

We mostly work in places where operators provide detailed data about their services. In places where there is no such official data, or where mappers have created a better data set than the official one, someone might want to route on the user-generated data in OpenStreetMap. The station groupings would be useful in that case. Even for purely visual (non-routing) map display, I can imagine the station groupings would assist in layout and labeling.

Regards,
Andrew



> On 1 Aug 2019, at 15:11, Joseph Eisenberg <[hidden email]> wrote:
>
> I'm trying to find out if the type=public_transport +
> public_transport=stop_area relation or *=stop_area_group relation is
> used by any developer or database user.
>
> These relations are supposed to group together features like all the
> platforms in a bus station or train station. However, it seems like
> these relations may not be necessary or useful for routing
> applications.
>
> Has anyone looked into them or know of any current use cases?
>
> Joseph
>
> _______________________________________________
> dev mailing list
> [hidden email]
> https://lists.openstreetmap.org/listinfo/dev


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