Isochrone API foot/hike returns very small areas

[Tjukanov]

Howdy! First of all: thank you for your excellent work on the project!

I have GraphHopper 2.0 running locally on my Ubuntu and I am using the isochrone API to create some accessibility areas around points. So I have been trying with walking and hiking, but the resulting isochrones seem to be very small. For example I have time_limit as 1800 (i.e. 30 minutes), but this results of areas which have a radius of roughly 400 meters). With 4 buckets and time limit of 1800 the biggest isochrone should be equivalent of 2 hours of walking, but those isochones seem to be roughly 2 kilometers.

If I check the web api, it should cover much bigger area (which seems more realistic):

So do I need to change the configs somehow or what am I doing wrong?

[karussell]

Thanks for your kind words! (and also thanks for occasionally spreading a good word about GraphHopper )

With 4 buckets and time limit of 1800 the biggest isochrone should be equivalent of 2 hours of walking

Buckets work differently: it will split the 1800 seconds into 4 similar sized buckets i.e. 450 * 4. See the documentation of the web service: graphhopper/docs/web/api-doc.md at master · graphhopper/graphhopper · GitHub

Does this resolve your issue or do you still observe problematic behaviour?

[Tjukanov]

Aaargh! How stupid from me! I was just looking at these web API docs where it wasn’t quite as clearly explained.

That should solve it! Thanks for the quick response and I will continue to spread the word whenever I can

[karussell]

Ah, ok, thanks!

Have fixed the documentation to our Directions API you linked https://github.com/graphhopper/directions-api-doc/commit/48103e6980926c4150f66282ce2d79f49c20440a

Furthermore I had to update the GH core documentation.

I will continue to spread the word whenever I can