[GRASS-user] Resample DEM to larger cells

Ken Mankoff mankoff at gmail.com
Tue Oct 1 15:08:10 PDT 2019

On 2019-10-01 at 17:48 -04, Rich Shepard <rshepard at appl-ecosys.com> wrote...
> There are 70 individual raster maps within the mask of the basin's
> watershed boundary. Am I correct that speed-issues aside, I need to
> run r.buildvrt so I have a single map as input to modules such as
> r.info (to identify the highest elevation), r.slope, and others? While
> I understand that a mask limits analyses to its area that is based on
> a single map extending beyond the mask and not a collection of 70
> 'tiles'. Am I correct?

r.univar can take multiple multiple maps as input and from that you could get max. r.slope and others would work best on a VRT or r.patch from the individual rasters.

> Are there alternatives to a virtual raster for situations like this?

r.patch? Or for loop over all the individual rasters w/ r.info to find the max? That won't work for r.slope because of edge effects.

A VRT is probably easiest / best.


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