Hi Pedro, I created a test case with the North Carolina sample dataset (by zooming in the GUI to the elevation map border and setting that as computational region):
# GRASS 7.2.2svn (nc_spm_08_grass7):~ > # set computational region around east elevation map border g.region n=216820 s=216770 w=644960 e=645040 res=10 -p # be sure that no data pixels are involved. r.out.ascii input=elevation output=- north: 216820 south: 216770 east: 645040 west: 644960 rows: 5 cols: 8 101.913734 102.054886 102.395638 102.597229 * * * * 101.821335 102.044083 102.331108 102.58638 * * * * 101.703033 101.955849 102.195648 102.54126 * * * * 101.56945 101.840988 102.152328 102.529175 * * * * 101.530174 101.792572 102.097748 102.477859 * * * * # export to AAIGrid format: r.out.gdal input=elevation output=elev.grd format=AAIGrid Driver <AAIGrid> does not support direct writing. Using MEM driver for intermediate dataset. Checking GDAL data type and nodata value... 100% Using GDAL data type <Float32> Input raster map contains cells with NULL-value (no-data). The value -nan will be used to represent no-data values in the input map. You can specify a nodata value with the nodata option. Exporting raster data to AAIGrid format... 100% r.out.gdal complete. File <elev.grd> created. # verification: cat elev.grd ncols 8 nrows 5 xllcorner 644960.000000000000 yllcorner 216770.000000000000 cellsize 10.000000000000 NODATA_value -nan 101.91373443603515625 102.0548858642578125 102.39563751220703125 102.59722900390625 -nan -nan -nan -nan 101.8213348388671875 102.0440826416015625 102.33110809326171875 102.5863800048828125 -nan -nan -nan -nan 101.703033447265625 101.95584869384765625 102.195648193359375 102.541259765625 -nan -nan -nan -nan 101.56945037841796875 101.8409881591796875 102.1523284912109375 102.5291748046875 -nan -nan -nan -nan 101.53017425537109375 101.792572021484375 102.097747802734375 102.4778594970703125 -nan -nan -nan -nan ... all fine and it works out of the box! Are you sure that you had any NULL cells at all? Note that the current computational region is respected for export. Markus _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user