Edzer, Thanks, i applied the patch and it works.
> The example you sent me looks nice! This area is in Switzerland, the mountains are Zuestoll and Schibenstoll (Churfirsten ridge), my favorit area for hiking and climbing. I calculated grids with 2m resolution with universial kriging, one grid with the breakline, the other without (files: ftp://ftp.geo.unizh.ch/pub/mhugent/gstat/zuestollwithbreak.png, zuestollwithoutbreak.png). While the one without breakline appears visually pleasing, the one with the breakline shows some strange spikes along lines. What could be the reason of this? And: how does the program handle such edges? Does it just use points on one side of the edge to calculate the value at a location? It looks as if the area has been subdivided into regions bounded by these strange artifacts. cheers, Marco
