Hello Grass users! I have the following problem:
Based on one raster map, i want to create a new map containing only eight cells - four in the corners of the map and four on the middle of the edges - with the category „1”. All other cells are supposed to be NULL-cells. I thought about doing this via r.mapcalc - yet i do not know if there is any possibility to manipulate only single cells with this command. It all comes down to the question if one cell in a GRASS raster layer actually contains information about its coordinates;(which i could include in a r.mapcalc command) - or if it is really only defined by the edges of the map, the resolution and the resulting number of cells? Sorry for the sort of noobish question, i think i don't yet have complete understanding of the GRASS raster format, though i read the related manual pages. I also know that i can reach the same result by simply digitizing a vector map with the points in question, then running v.to.rast. But as i want to make this operation part of a shell script, i'm eager to avoid (1) most interactive operations and (2) the way to the vector format and back again. Point 1 i could of course avoid by using v.edit, but there is still point 2. Would be glad for any help! Thanks, Levent -- View this message in context: http://osgeo-org.1803224.n2.nabble.com/Extract-single-pixels-with-r-mapcalc-tp5935168p5935168.html Sent from the Grass - Users mailing list archive at Nabble.com. _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
