Stitching together rasters

GRASS GRASS user
1

From grass-lists-owner@max.cecer.army.mil Thu Aug 18 08:24:01 1994
Date: Thu, 18 Aug 94 16:18 BST-1
From: nra@cix.compulink.co.uk (N R A )
Subject: Stitching together rasters
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Is there any easy way to 'stitch' together 2 (or more) rasters maps -
this is mainly in regard to our use of r.watershed to produce an aspect
map for the whole region. On our poor little Sun IPX doing it in one go
would take forever, but I estimate that doing it as say about 4x10
smaller blocks would only take about 40 hours. This is only really of any
use if I can then somehow combine the small blocks back into one 'aspect'
map.

Cheers,

Steve Culshaw
NRA North West
e-mail : nra@cix.compulink.co.uk (use this for general usage)
or sculshaw@cix.compulink.co.uk (Private - only checked at best
biweekly)

r.patch will do that. It combines raster maps into one map. Areas of
"no data" in the first map will be filled with data from the second.
Areas of no data in the first and second will be filled by the third and
so on. Be sure to set your region to include all of the input maps.

-Sue Huse
REGIS
UC Berkeley