On Sun, Mar 25, 2012 at 2:59 PM, Filipe Silva Dias <[email protected]> wrote: > Thanks. Out of curiosity and tried with Grass 7 with -m (and 30 m > resolution) and I obtained this error message: > > r.watershed -m elevation=DemPT2@Grass7 threshold=10000 > stream=streams > SECTION 1 beginning: Initiating Variables. 5 sections total. > SECTION 1a: Mark masked and NULL cells > SECTION 1b: Determining Offmap Flow. > SECTION 2: A* Search. > SECTION 3: Accumulating Surface Flow with MFD. > SECTION 4: Watershed determination. > SECTION 5: Closing Maps. > ERROR: Rast_make_random_colors: min (1) > max (0)
Apparently no basins were determined, probably because the threshold of 10000 for flow accumulation was never reached. Maybe the current region was either too small or did not cover parts of the DEM DemPT2? BTW, if you want to try out GRASS 7 in a separate mapset, you don't need to copy over the DEM if you just want to read it. Within the mapset Grass7, the following commands should work: g.region -p rast=DemPt@ETRS89 r.watershed elevation=DemPt@ETRS89 stream=stream threshold=10000 -m Markus M > > Subprocess failed with exit code 1 > category information for [streams] in [Grass7] missing or invalid > > > > > On Sun, Mar 25, 2012 at 11:49 AM, Markus Metz > <[email protected]> wrote: >> >> On Sun, Mar 25, 2012 at 12:30 PM, Filipe Silva Dias >> <[email protected]> wrote: >> > I switched the resolution from 30x30 to 100x100 and now it works. >> > Problem >> > solved. >> > >> > >> > On Sun, Mar 25, 2012 at 11:12 AM, Filipe Silva Dias >> > <[email protected]> >> > wrote: >> >> >> >> I'm using GRASS 6.4.2 and I'm on Windows 7 >> >> >> >> >> >> On Sun, Mar 25, 2012 at 11:11 AM, Filipe Silva Dias >> >> <[email protected]> wrote: >> >>> >> >>> Dear all >> >>> >> >>> I'm trying to run r.watershed on a ASTER DEM (with the size of >> >>> Portugal) >> >>> but I'm getting this error: >> >>> >> >>> r.watershed elevation=DemPt@ETRS89 stream=stream >> >>> threshold=10000 >> >>> SECTION 1a (of 5): Initiating Memory. >> >>> ERROR: G_malloc: unable to allocate 1515173064 bytes at >> >>> init_vars.c:134 >> >>> Subprocess failed with exit code 1 >> >>> category information for [stream] in [ETRS89] missing or invalid >> >>> >> >>> What am I doing wrong? >> >>> >> As you figured out already, the region, i.e. number of cells was too >> large. In order to run r.watershed with that region (Portugal at 30m >> resolution) on Windows, you would need GRASS 7 and run r.watershed >> with the -m option. >> >> Markus M > > _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
