On Wed, 2009-07-08 at 09:51 -0700, Dylan Beaudette wrote: > On Wednesday 08 July 2009, Nikos Alexandris wrote: > > There is something strange with the values though (they expand from min > > = -32687 max = 32645). Don't have the time to dig further, maybe there > > are details in the meta-data about it (!?). > > This looks like an overflow problem. Could it be that this file contains > unsigned 16 / 32 bit integers, but is being read in as signed 16 bit > integers?
Probably you are right Dylan. In the meta-data it is written: << Level 2 DEM: Level 2 DEMs may contain void areas due to interruptions to contours in the source graphic or DLG. Void area elevation grid posts are assigned the value of -32,767. >> * This means that original data are for sure Signed (probably Int16-bit... ?). * gdal reads the data correctly (look previous post of mine) as: Band 1 Block=20x4 Type=Int16, ColorInterp=Undefined Min=0.000 Max=1371.000 NoData Value=-32768 * grass reports the range of the imported data as: r.info dem250 -tr min=-32687 max=32645 datatype=CELL * The data show up correctly in GRASS: g.region rast=dem250 && r.colors dem250 color=terrain && d.mon x0 && d.rast dem250 If we accept min=-32687 that was assigned to be nodata, what is this max=32645? Nikos _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user