Markus Metz wrote: > But it calls r.mapcalc, e.g. in lines 151-153. If k is > integer and not float, r.mapcalc will do integer division. > Equivalent for lines 159, 162, 165. This could be fixed by > casting the numerator to double with double(). or just put * 1.0 somewhere. is there sample data available showing the problem? Hamish