This is not much consolation but try using r.resample on the file.
I've found it helps. I have no idea why this happens unfortunately.
Good Luck
Teresa Hansen
Ogden Professional Service
Fort Lewis, Washington USA
From grass-lists-owner@moon.cecer.army.mil Tue Jun 27 09:54:53 1995
From: S.Cox@solo.ned.dem.csiro.au (Simon Cox)
Subject: Why are r.patch'ed files so slooowwww?I have a bunch of not-large rasters (240rx360c) which tile together to
cover a much larger area. I thought it would be useful to use r.patch to
stitch these together so I could subset it just using g.region, etc.
However, when I d.rast the resultant file it is soooo slooowwww it is not
funny. I can display _all_ the tiles in a much much much shorter time.
What is the story here? any ideas?(I have tried 9-at-a-time, 4-at-a-time, 2-at-a-time, always being careful
to set the region to exactly cover the contiguous area only, but horrible
performance in all cases.)Thanks for your suggestions. Simon Cox
___________________________________________________________
Dr Simon Cox __ \
CSIRO Exploration & Mining ,~' L_|\ Australian
39 Fairway, PO Box 437, ;-' \ Geodynamics
Nedlands, WA 6009 Australia ( \ Cooperative
Phone +61 9 389 8421 + ___ / Research
Fax +61 9 389 1906 L~~' "\__/ Centre
simon@ned.dem.csiro.au W
AGCRC info>> http://www.dem.csiro.au/simon/crc/intro.html
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