[GRASSLIST:657] Re: Shortest distance routing

[Miha STAUT]

>can somebody point me to some information on how to work with network (esp. 
>road network) analysis in GRASS. Let's consider I have a vector databases 
>of a city's road network and want to find out the shortest distance between 
>point A and B.
>
>All I can find by looking at the docs and searching through google are more 
>or less surface runoff routing examples.

It could be taking a bit longer but:

v.to.rast in=road.map out=road.map
# all the roads have the same id or for time distance different speed limits 
different inverse factor so: 1/ # (speed limit)
r.coast in=road.map out=road.distance
r.drain in=road.distance out=shortest.path coord=x,y

Hope it helps.

Miha Staut

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