[GRASS-user] scripting mapcalc
neteler at osgeo.org
Thu Mar 5 13:46:06 EST 2009
On Thu, Mar 5, 2009 at 3:42 PM, achim <ak7 at jupiter.uni-freiburg.de> wrote:
> did someone tried -like me- to use r.mapcalc in a script inside an
> I cannot pass changing variables $old, $new like:
> r.mapcalc 'river=if(river=$old,$new,null())'
> its because of the '', which are needed because if the if-statement.
If you use single quotes '$foo', then the variables are protected.
You need to use double quotes: "$foo":
PS: In GRASS 7, you need white space (at least) before the equal sign:
r.mapcalc "river = if(river=$old,$new,null())"
(see its manual)
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