[GRASS-user] AAIGrid import-export problem

[Martin Wegmann]

Hello Dylan,

On Friday 01 December 2006 19:23, Dylan Beaudette wrote:
[...]
> I am interested in hearing about the issues you have observed with
> r.resamp.stats.
>
> I too have noticed some odd behaviour when the input/output resolution is
> the same : a systematic shift occurs.
>
> an example with spearfish60:
>
> g.region rast=elevation.dem
> r.resamp.stats in=elevation.dem out=r method=average
> d.rast elevation.dem
> r.mapcalc "rd = float(elevation.dem - r)"
> d.rast rd
> r.info rd

hmm, interesting - I assume it is the same behaviour and due to the larger 
area I am working on, my shift is more pronounced.
Attached a jpg of r and elevation.dem correlation (Moving Window size 3x3 
multiplied with 1000) - the deviation from 1000 (or corr. val 1) is just 
present in parts of the image - I would have assumed that the whole image has 
a constant deviation from 1000, hence there might be another error.

Martin




> Cheers,
>
> Dylan
>
> On Friday 01 December 2006 08:34, Martin Wegmann wrote:
> > I tested various r.out.gdal settings (-r is a very handy function! -
> > thanks Hamish) and found no errors using various files.
> > Finally I ended up doing further test with r.resamp.stats where I found
> > the problem.
> > Hence r.out.gdal shows no inconsistency but r.resamp.stats - I'll post
> > another message concerning this behaviour in a few minutes.
> >
> > Martin
> >
> > On Friday 01 December 2006 01:51, Hamish wrote:
> > > Martin Wegmann wrote:
> > > > On Thursday 30 November 2006 13:43, Wolfgang wrote:
> > > > > have you changed g.region to your new settings before export?
> > > >
> > > > I changed g.region res. during the r.resamp.stats but for export of
> > > > the two raster g.region wasn't changed
> > > >
> > > > BTW r.info of the two raster gives same res/coord. for both.
> > >
> > > what about with using the new region sensitive GDAL output? (resamples)
> > > "r.out.gdal -r"
> > >
> > >
> > > r.in.gdal out=NAME
> > > g.region rast=NAME
> > > r.out.gdal -r in=NAME
> > >
> > >
> > > ?
> > > Hamish
> >
> > _______________________________________________
> > grassuser mailing list
> > grassuser at grass.itc.it
> > http://grass.itc.it/mailman/listinfo/grassuser
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