[GRASSLIST:724] Re: Negative elevations

[Daniel Victoria]

Hi Kurt,

I'd try selecting the negative values, multiplying by
-1 and then adding to the original raster map,
something like

r.mapcalc 'neg_mask=if(rast < 0, rast, 0)'
r.mapcalc 'mask2=neg_mask*-1'
r.mapcalc 'new_rast=rast+mask2'

haven't tested it but that's my idea of how to do
it...

Cheers

Daniel

--- Kurt Springs <ferret_bard at mac.com> wrote:
> Hi folks,
> 
> As if you couldn't guess.   New question.
> 
> Some one opened one of the dxf files in ArcView.  It
> looked like it had
> negative elevations.  When I ran v.surf.rst then
> v.color there was an
> indication that some of my attributes were negative.
>  Is there a way to
> correct this.  Maybe a way to add the the negative
> number making the
> negatives zero?
> 
> Also is there a way to be sure the elevations are
> set to metres?
> 
> Kurt
> 


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