Apparentely, gstat does not handle grass null values. At least, I've found problems with gstat if null values are not masked out.
Therefore, it's important to set a proper mask. Something like: r.mapcalc "MASK = if(isnull(raster),null(),1)" will create a MASK for null values or inlude them in the active mask. Also, thanks to Edzer, Im using the following line command style for gstat in grass scripts: gstat -e semivariogram -c $cut -i $wid dum > $nout Hope this helps (and that I'm not wrong). Agus Dr. Agustin Lobo Instituto de Ciencias de la Tierra (CSIC) Lluis Sole Sabaris s/n 08028 Barcelona SPAIN tel 34 93409 5410 fax 34 93411 0012 [EMAIL PROTECTED]
