On Thu, Feb 6, 2014 at 1:14 PM, Blumentrath, Stefan <[email protected]> wrote: > Dear all, > > I am testing, trying, learning GRASS 7`s hydrology moduls at the moment. And > I am very, very satisfied with the available tools. r.watershed managed to > process a really big elevation model (150,000 x 120,000 pixels), which is > amazing.
Wow! Please consider to add a note to http://grasswiki.osgeo.org/wiki/GRASS_GIS_Performance#Large_raster_data_processing (or in a blog entry or the like) > However, when I use r.hydrodem addon on the same big grid with 150,000 x > 120,000 pixels (with the memory option) I get the following warning (and > finally error) message: > > r.hydrodem input=dem_10m memory=10000 output=dem_10m _hydro ... > WARNING: segment_format(fd,1,-221837149,1,262144,16): illegal value(s) This is an integer overflow of ncols etc: [neteler@pgis_north r.hydrodem]$ grep nrows seg.c seg_open(SSEG *sseg, int nrows, int ncols, int row_in_seg, int col_in_seg, In r.watershed it is defined differently: [neteler@pgis_north r.watershed]$ grep nrows seg/sseg_open.c seg_open(SSEG * sseg, GW_LARGE_INT nrows, GW_LARGE_INT ncols, int row_in_seg, int col_in_seg, if (0 > (errflag = segment_format(fd, nrows, ncols, I suppose that this is an "easy" fix given the experience of r.watershed. To not interfere, I'll leave the change to the module author. Best, markusN _______________________________________________ grass-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-dev
