Stefan Neumeier wrote: > Dear all, > > I am relatively new to GRASS so maybe I am just missing some important step > in between. > What I want to do is to calculate a "simple" distance matrix from x start > points (polygon-raster centroids) > to x end points (specific locations e.g. hospitals) based on a route > network. > > In a first step I prepared the network so that every start- and end point > lies on the network (via v.net, option connect). > In a second step I created a point input textfile to use in v.net.path (ID > startX startY endX endY) wit several thousand records. > > Testing the shortest path calculation for one, two or three coordinate pairs > read in from the point input file works > as one would expect and I get a new vector layer depicting the pathes from > the start points to the end-points based on the > road network. > > But if the number of points in the input point file exceeds 4 coordinate > pairs GRASS calculates all consecutive > distances seemingly as airline distances instead of road based distances (In > the output vector layer the pairs of points > are connected with a straight line only). > This should be fixed in recent versions of GRASS [1,2]
Markus M [1] http://josef.fsv.cvut.cz/wingrass/grass64/ [2] http://josef.fsv.cvut.cz/wingrass/grass65/ _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user