[GRASS-dev] r.mapcalc bug on max and min?

Pietro peter.zamb at gmail.com
Mon Oct 6 06:07:09 PDT 2014

On Mon, Oct 6, 2014 at 2:25 PM, Anna Petrášová <kratochanna at gmail.com> wrote:
> On Mon, Oct 6, 2014 at 4:51 AM, Pietro <peter.zamb at gmail.com> wrote:
>> Again everything is NULL, I'm doing something wrong or it is a bug?
> Glynn could perhaps give you some more precise comment, but basically, max
> doesn't operate on the entire map but only on the current cell. So for
> example, r.macalc "map_max = max(elevation1, elevation2, elevation3)"
> creates a map where each cell is the largest value of the corresponding
> cells in the 3 elevation maps.

Ahh, I misunderstood the documentation I thought it was not pixel by
pixel but for the whole raster map...
now the results are explained! :-)

Perhaps we could add two new functions, like: rmin and rmax that stay
for range min and range max that give this information, do you think
could be useful?

More information about the grass-dev mailing list