Thanks Markus, Let me make sure I understand. For best results I need to set the resolution to 10m for the 1/3 arcsec. With the region set as it is (most of Northern New England) when I do this I run out of memory. To over come this, I can set the region to just encompass just the NED13_01 subregion. Would it look like g.region zoom=NED13_01 align=NED13_01?
Might this also solve another problem I am having with r.watershed. When the various functions are run, I have the map, plus "stuff" in the NULL area out side the map region. Thanks for the help. Kurt On May 24, 2010, at 4:37 AM, Markus Metz wrote: > On Sun, May 23, 2010 at 8:10 PM, Kurt Springs <ferret_b...@mac.com> wrote: >> Problem was the resolution it starts working when I set it to 100m. The dem >> is ~69 x 27 km. > > Apparently, the dem has a resolution of 1/3 arcsec (~10m), maybe > reprojected and resampled. With these extends, there would be about > 186 million cells in the input map which is not a lot. I have > successfully processed regions with ~250 million cells in memory and > ~500 million cells in segmented mode. Make sure the current > computational region matches the resolution of the input dem and the > extends of the current computational region do not exceed the extends > of the input map. Setting the computational region to a smaller area > within the dem coverage is fine, as long as g.region -p align=NED13_01 > is used after adjusting the extends. A resolution of 100m throws away > a lot of the information present in the original dem. > > >> Thanks >> On May 23, 2010, at 12:00 PM, Rich Shepard wrote: >> >> On Sat, 22 May 2010, Kurt Springs wrote: >> >> ERROR: G_malloc: unable to allocate 18446744070980740804 bytes at ... >> >> ^^^^^^^^^^^^^^^^^^^^ >> >> Any idea what I'm doing wrong? >> >> Kurt, >> >> Look at the amount of memory your file wants to be allocated: several >> Petabytes. How much area is covered by that DEM and at what resolution? Even >> with GRASS compiled for large file support your file is _way_ too large. >> >> Rich >> >> _______________________________________________ >> grass-user mailing list >> grass-user@lists.osgeo.org >> http://lists.osgeo.org/mailman/listinfo/grass-user >> >> _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user