[GRASSLIST:2325] Re: Removing a section of a raster map

[Rich Shepard]

On Wed, 8 Aug 2001, Hal Mueller wrote:

> I think the key is r.mask.  You can derive the mask by comparing
> layer with protrusion to layer without protrusion.  Or maybe just by
> looking at layer without protrusion.

  I don't have a copy of the whole map without the protrusion. It might be
quicker for me to regenerate one.

> I would try
>
> r.mapcalc to make a binary raster, 1 where I want data and 0 where I don't
>
> r.mask set the mask to be that binary I just made
>
> r.mapcalc newrast=rastwithprotrusion

  Thanks, Hal. I was thinking along these lines, but with only the one map
now in existence, I was hoping there'd be a way to manipulate that.

Rich

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