[GRASS-user] using r.mapcalc on a 100 rasters to produce one output (a temporal set of rasters)

[Markus Neteler]

On Thu, Aug 19, 2010 at 2:50 AM, m k <ytrapaet at hotmail.com> wrote:
> My apologies if this is a repeat post, but i think my question did not get
> delivered last try. (I'm new here!)
>
> I am looking for a way for GRASS to do create one output raster based on the
> analysis of say 100 rasters (same spatial coordanates, but each raster has
> an equal time interval between them).
>
> For example if I have 100 rasters that have only 0's and 1's, and I want
> to calculate an output raster that shows how long it took each cell to first
> acquire a value of 1. Another example: sums up all 100 rasters to one output
> raster.
> From what I've gathered, I think that r.mapcalc will do the necessary
> functions, but I cannot find an example where it is processing 100s of
> rasters in a temporal set.

The r.series module is the right tool for this:
http://grass.osgeo.org/grass64/manuals/html64_user/r.series.html

I have added some hints to
http://grass.osgeo.org/wiki/Time_series

Markus