[GRASS-user] extract by attribute from a dem

[Hamish]

[cc the user list]

nishith wrote:
> well thanks I now understand the region settings.
> About the dem - could it be some error ?!? I downloaded it from esdi .
> It is srtm data. I included the srtm geotiff in one of my post could
> someone try out the dem for me and see if it works ? I can see there
> are areas below 20 degrees and that should be reported by r.mapcalc !
...
> Thanks a ton,
> I got it right this time.
> Actually it was the g.region problem.
> One more thing. I donot know whatz the problem , I generate the slope
> and get a whole lot of negative values. Now what are these ? values like
> -34.5 and so on ! Well is the dem alright to start with. Set's me
> wondering ?!?!

Have you imported a lat/lon dataset into a non-lat/lon location?
what does this say:
GRASS> g.proj -p
GRASS> g.region -p

that might explain the crazy slope values.

??
Hamish