On Wed, Feb 11, 2009 at 5:03 PM, Dylan Beaudette <debeaude...@ucdavis.edu> wrote: > On Wednesday 11 February 2009, MORREALE Jean Roc wrote: >> Hamish a écrit : >> > Kurt Springs wrote: >> >> Does anyone know how to do Thiessen Polygons in GRASS? >> >> >> >> I need to use them around various types of megalithic tomb >> >> sites that are in point vector files. >> > >> > v.voronoi >> > >> > >> > there is some replacement test code to look at in grass-addons as well: >> > http://trac.osgeo.org/grass/browser/grass-addons/vector/voronoi >> >> While we are on this topic, is there a way to get a weigthed voronoi >> diagram using grass ? >> >> The ability to rank a point to tune the area's influence would be great, >> for that purpose I've been using an arcgis'extension* but with grass it >> is not possible**. Is there a way to get a similar result ? >> >> *http://www.geog.unt.edu/~pdong/software.htm >> **http://osdir.com/ml/gis.grass.user/2004-04/msg00036.html >> >> Regards, >> MORREALE Jean Roc >
Now that I have read about 'weighted voronoi diagrams', I wonder if a combination of r.cost + r.mapcalc would solve this problem. Something along those lines is demonstrated here: http://casoilresource.lawr.ucdavis.edu/drupal/node/288 This example isn't quite what is requested, although using r.cost with start=point_i, and stop=neighbor_points (derived from v.delaunay / v.distance?) may work. It would then be a little more work to convert the weighted-distance rasters into polygons, and link back to the original attribute tables... but (hopefully) not outside the realm of possibility via a script. Cheers, Dylan _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user