Open kofronpi opened 6 years ago
Hello,
I had a brief look at it, but I do not manage to go at 8am from your starting point to a point in Paris before 9am, even when computing a journey (walking as fallback mode, and using public-transport).
What type of journey do you have in mind? A journey from that exact coordinates arriving before 9am (8am + 3600s), to where in Paris and using what transport?
I see some reasons why it wouldn't work correctly (problem in transport data, in street-network data, bug), but I don't see how to investigate without a simple journey example that you think should work. You can have a look at that section of doc (if it's not already the case) : https://doc.navitia.io/#isochrones-currently-in-beta especially the part "Understand the resulting isochrone"
Please also keep in mind that starting from specific coordinates, Navitia first computes a walking fallback (one have to walk to the station, and it can be quite long). If you provide a "city id" as a starting point, result could be wider because (most of the time) walking is not considered necessary in that case : https://api.navitia.io/v1/coverage/fr-idf/isochrones?boundary_duration%5B%5D=3600&datetime=20180522T080000&forbidden_uris%5B%5D=physical_mode%3AAir&forbidden_uris%5B%5D=physical_mode%3ATaxi&from=admin%3Afr%3A78297&
@pbougue an example from navitia's journey API:
Paris 15 -> Versailles
1) 7:17 am train C - Gare de Versailles Château - Rive Gauche (Versailles) from Gare d'Issy Val de Seine (Issy-les-Moulineaux) at 07:17 to Gare de Versailles Château - Rive Gauche (Versailles) at 07:35 during 18min 2) BUS 39-12 - technocentre Trou Berger (Guyancourt) from Gare de Versailles-Chantiers (Versailles) at 07:35 to Frères Perret (Guyancourt) at 07:52 during 17min
or Versailles -> Paris 15
1) Bus 440 - Versailles Château - Rive Gauche Gare (Versailles) from Dampierre (Guyancourt) at 07:20 to Versailles Château - Rive Gauche Gare (Versailles) at 07:33 during 13min 2) Train C - Gare de Versailles Chantiers (Versailles) from Gare de Versailles Château - Rive Gauche (Versailles) at 07:55 to Gare d'Issy (Issy-les-Moulineaux) at 08:10 during 15min
Even with walking times included, and in both directions, Paris 15 should be roughly accessible and it's far from there. I took the farthest city from the starting point to show that other, closer cities should be included too.
Also, lately I noted a tendency to regularly "skip" cities accessible by TER in isochrones results. Thank you for your help and I'm willing to help dig more into it :)
@kofronpi if you have the exact Navitia call for journeys (or any call), it would be easier to talk/debug. Anyway, from what you tell here is what I can explain.
First (it's in doc maybe not clear enough, we have to see if it can be improved) :
So, from what you say:
@pbougue thanks for your help, I will have a look into this.
Hello,
Requests for transit isochrones south of Paris (tested in Saclay, Guyancourt...) give me wrong results ( small isochrones, very underestimated accessibility: Paris never reached although it can be)
Here is a sample request:
https://api.navitia.io/v1/coverage/fr-idf/isochrones?boundary_duration%5B%5D=2700&datetime=20180522T080000&forbidden_uris%5B%5D=physical_mode%3AAir&forbidden_uris%5B%5D=physical_mode%3ATaxi&from=2.072035%3B48.769893
And the isochrone as a result: (40minutes)
And for 60 minutes:
It's the same either with "from" or "to" parameters (departure after / arrival before), and with other dates (I first thought it was because next Monday was a public holiday).
Thanks for your help.