[GRASS-user] Temporal Analysis

[Martin Wegmann]

hello Nikos,

I would combine r.mapcalc and r.series. With r.mapcalc you could extract 
values below a certain threshold and do the r.series analysis based on this 
new dataset.

e.g.
for i in `g.mlist pattern='pattern_of_your_raster*'` ; do 
r.mapcalc "$i_new = if($i < threshold, $i, null())"
; done

r.series input="`g.mlist pattern='*_new' sep=,`"  output=results method=sum

regards, Martin

On Montag, 7. Juni 2010 18:38:38 Nikos Dumakis wrote:
> Thank you Martin.
> 
> I realized that one of the functions that I need, (counter of values bellow
> a certain threshold) is not available in r.series. Do you know, or do you
> have any suggestion, how to perform this?
> Thanks
> 
> Best regards
> Nikos
> 
> On Mon, Jun 7, 2010 at 1:12 PM, Martin Wegmann <
> 
> martin.wegmann at uni-wuerzburg.de> wrote:
> > Hello Nikos,
> > 
> > just give r.series a try.
> > 
> > regards, Martin
> > 
> > On Montag, 7. Juni 2010 14:06:17 Nikos Dumakis wrote:
> > > Greetings
> > > 
> > > 
> > > I have to do some simple-statistical TEMPORAL analysis between a long
> > > data-series. I mean, I have do some temporal average for each pixel,
> > > minimum and max. Instead of doing this statistical- analysis for all
> > > pixels in an image, I have to do this analysis for each image-pixel
> > > along its temporal series.
> > > 
> > > Is there any function to do this? Or as anyone tried ?
> > > Thanks
> > > Nikos
> > 
> > --
> > Dr. Martin Wegmann
> > 
> > University of Wuerzburg
> > Institute of Geography
> > Department of Remote Sensing
> > Remote Sensing and Ecosystem Research
> > Am Hubland
> > 97074 Wuerzburg, Germany
> > @
> > German Aerospace Center (DLR)
> > German Remote Sensing Data Center (DFD)
> > 
> > Phone:  +49-(0)931-31-83446
> > Fax:       +49-(0)931-31-84961
> > Email:  martin.wegmann at uni-wuerzburg.de
> > url: http://www.remote-sensing.uni-wuerzburg.de
> > url: http://www.dlr.de/caf
> > url: http://www.global-change-ecology.de

-- 
Dr. Martin Wegmann

University of Wuerzburg
Institute of Geography
Department of Remote Sensing
Remote Sensing and Ecosystem Research
Am Hubland
97074 Wuerzburg, Germany
@
German Aerospace Center (DLR)
German Remote Sensing Data Center (DFD)

Phone:  +49-(0)931-31-83446
Fax:       +49-(0)931-31-84961
Email:  martin.wegmann at uni-wuerzburg.de
url: http://www.remote-sensing.uni-wuerzburg.de
url: http://www.dlr.de/caf
url: http://www.global-change-ecology.de