[GRASS-user] Values from multiple raster - "to link" together

[Alex Mandel]

On 11/15/2010 10:59 AM, Gabriele N. wrote:
> 
> Hello everyone.
> I have to solve a problem already discussed here:
> http://osgeo-org.1803224.n2.nabble.com/r-mapcalc-concatenates-values-td1884970.html#a1884973
> 
> In summary, I have for example 3 maps A, B, C.
> I need to combine the values of the overlapping cells. For example if I have
> a cell in the map "A" with value 11, in the corresponding cell of the map
> "B" I have 2222 and the corresponding cell of the map "C" is 3333.
> In output I would like to have a map that has a value in that cell
> 1122223333.
> I tried with r.mapcalc, but without Successfully.
> 
> Help?
> 
> Thanks
> 
> Gabriele

The quick way to do this classically is using reclassification
techniques. Are the number of digits the same for all of A, B and C?
If so
(A * 100000000)+ (B*10000)+C would get you that answer

Usually with Raster processing you have to think of ways to solve using
only math, hence concatenation not working. Now if you converted your
grids to polygons that would be totally different.

Thanks,
Alex