GRASS simply returns the same point back, since the closest node to A is A. If I use patch first, then the from and to maps in v.distance must be the same, unless I am misunderstanding something.
The vector map containing the intersections (the set of points B) contains both points (created using v.net nodes) and lines (the original road network). I can get the nearest point using v.distance, but this uses straight-line distance, not the distance along the road. Although v.distance offers the "to_along" option, there does not appear to be anywhere to specify which vector contains the road network. And it seems that v.net.path requires that both the start and end points must be known a priori, and I only have the start point. I am trying to find the end point (the nearest intersection). I am stuck, but I think I am missing something important here. Markus Neteler OSGeo wrote: > > On Sat, Dec 20, 2008 at 9:04 PM, Ryan R. Rosario <[email protected]> > wrote: >> >> I have two vector maps consisting of points and a vector map containing a >> road network. Given a point A, I want to find the nearest point B along >> the >> road network, for each A. >> >> I have looked at v.net.path and v.distance's to_along but they seem to >> require B to be known. How can I do this? > > Suggestion: v.patch first, then the others. > > Markus > _______________________________________________ > grass-user mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/grass-user > > -- View this message in context: http://www.nabble.com/Finding-Nearest-Intersection-%28point%29-on-Road-Network-tp21108480p21155428.html Sent from the Grass - Users mailing list archive at Nabble.com. _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
