[GRASS5] r.patch and NULL data

[Glynn Clements]

Markus Neteler wrote:

> at time I face the problem that r.patch does not work as I
> expect...
> 
> Idea: patch a converted sites map to a underlying raster map
> in this small data set (11 kb):
> 
> http://grass.itc.it/statsgrass/maas_grass_location.tar.gz
> Maas river bank soil contamination (UTM)
> 
> What I did:
> 
> grass5 ~/grassdata/maas/user1/
> 1. s.to.rast in=Zn out=zn
> 2. r.patch zn,maasbank out=fin
> 
> result only contains the raster cells from zn, the maasbank
> area is not visible (fin = zn).
> 
> Also
>  r.mapcalc fin="if(isnull(zn),maasbank,zn)"
> doesn't help.
> 
> Is it my mistake (which)?

I find that both r.patch and r.mapcalc work. With r.patch, the
"maasbank" cells are white; with r.patch, they are yellow.

-- 
Glynn Clements <glynn.clements at virgin.net>