Hamish wrote: > r.mapcalc map.red = r#map > r.mapcalc map.green = g#map > r.mapcalc map.blue = b#map This: r.mapcalc "map.red = r#map ; map.green = g#map ; map.blue = b#map" is more efficient, as it only reads the input map once. -- Glynn Clements <glynn at gclements.plus.com>