[GRASS-user] r.mapcalc appears to have changed behavior
Hamish
hamish_b at yahoo.com
Mon Sep 26 23:59:14 EDT 2011
Jim wrote:
> I had made a number of scripts that worked fine in the 6.4.0 build 6
> but appear to have problems with the same code in later revisions:
> The method used to take about 6-8 secs and produce about what you would
> expect on the screen. Now the same calculation takes 0 seconds the file
> is radically changed. See the before and after below.
the computational region is wrong. use g.region to fix it.
> r.mapcalc na_dem_sub_20 = na_dem_input - 20
to match the region to the input map, first run:
g.region rast=na_dem_input
compare:
> Rows: 8384
> Columns: 9102
...
> Rows: 1
> Columns: 1
> Total Cells: 1
Hamish
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