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The way that I would try to answer your original question is to add a field to your roads and update it with a count of vertices. Add a Long Integer field Calculate that field using the Python parser to be equal to !shape.pointcount!, You can then use the vertex count field as, or to contribute to, your impedance field. You'll need to think about ...


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If you have a well made road graph shape (with from and to nodes), you can use my qgis processing scripts at https://github.com/chourmo/QGIS-Transit-tools For batch starting points, use Shortest-times car If you want to find times from start to end, make a lines files and use Shortest-path car


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I would suggest Grass GIS. The v.net package is a pretty powerful tool. Grass can be a bit tricky to get going on but with a tutorial or two you should be OK. You will also need to interpret the matrix result that will be ~200 by ~200 with the distances. Export to excel, import with Python, etc. and do what needs doing with it. ...


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You can find multiple versions of routing scripts which use the QGIS network analysis library in my Github repository, e.g. https://github.com/anitagraser/QGIS-Processing-tools/blob/master/2.2/scripts/point_layer_to_route.py which converts an ordered set of points into a route. None of the scripts use the intersections of an input line with the network. ...


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According to Karussells comment, one can define a weighting of the street map graph dependent on the distances of the points to the nearest edges (streets) and then simply run a Dijkstra on that weighted graph. Since pgRouting (an extension of PostGIS for routing) allows to run Dijkstra on an arbitrary weighted graph, the only thing one needs to do is define ...


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If you are into Java and want Flexibility, Graphhopper is an excellent alternative. Peter, the project lead, actively encourages extensions and changes and the community is very responsive. Graphhopper works differently to Pgrouting (I use both) and it is extremely fast. Instead of using a PostGis database, Graphhopper builds its graphs direct form the .pbf ...


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AFAIK there is currently no real alternative to OTP, esp. for supporting big networks. See also: https://wiki.openstreetmap.org/wiki/GTFS


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Since you appear to use a vector representation of the routes, you may first split it into short segments (in order to later have a representative view on slope etc), using v.split; then add a new column to the attribute table of that road map: "slope double precision" using v.db.addcolumn; eventually upload the respective road segment slopes to the ...


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Ok,so I think I found an answer to my problem. Basically, hierarchy is used in long-distance networks where a lot of routes must be solved. Say if you are traveling from Vancouver to Seattle, hierarchy will help you solve the route faster. Instead of solving for all small routes, the solver will solve based on hierarchy and excludes smaller roads until it ...


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pgRouting does not provide such a functionality. There is a semi-automated tool to align GPS points with OSM data named "Slide": http://labs.strava.com/slide/ It's released under open source license and the algorithm could be also implemented as pgRouting function (either as contribution or with funding).


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Ok, I tried everything again. I am working in a database so I created separate feature classes and removed all costs but length ( you need to at least have one to run the network ) yet ,it is not working. So I even made the network much simpler, I can't humanly make it simpler than this. Attached are the pictures: Note: the red line hierarchy :1 The green ...


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Have you followed the guidelines on these pages? http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//004700000057000000 http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//004700000020000000 "Using hierarchy by default As long as the network dataset has a hierarchy attribute, you can set any network analysis layer you create to use ...



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