On 06/02/12 12:46, Johannes Radinger wrote:
The r.thin process is an important step (as recommended also in the manual) and should not be skipped at all!
In general, I agree with you, but I'm not sure that v.to.rast + r.to.vect would profit of r.thin in the middle, since v.to.rast already should provide a thinned line. AFAIU r.thin is useful when you have raster lines produced by something else than v.to.rast.
Maybe I just see something wrong..anyway i thought about testing the stability in a loop, but I got stucked in the correct map calc operation. What is the correct (boolean) operator to get:
>
1) NULL + NULL = NULL
> 2) not NULL + not NULL = NULL > 3) not NULL + NULL = 1
4) NULL + not NULL = 1
How about (untested): if( (isnull(A) && isnull(B)) || (!isnull(A) && !isnull(B)), null(), 1) Moritz _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
