Why are r.patch'ed files so slooowwww?

[Teresa Hansen]

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 at moon.cecer.army.mil Tue Jun 27 09:54:53 1995
> From: S.Cox at 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
> 
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