[GRASSLIST:6079] resampling to fractional cover

GRASS GRASS user
1

Hello,

I am using GRASS 6.0 cvs on Mac OS 10.3.

I have a very high-resolution raster map with category data. I want to make a series of coarse resolution raster maps from this base map that contain the fraction of each coarse-resolution grid cell that is occupied by a particular category in the fine-resolution base map.

I have looked at r.average but don't really see how to approach this problem (or even if it would be possible with GRASS).

Any advice or examples would be much appreciated.

Thanks for the help,

Jed Kaplan

2

Jed

You could write a script which would reduce your resolution by a given factor (g.region res=... -p) and r.resamp'led your map in a loop.

Maciek

----- Original Message ----- From: "Jed O. Kaplan" <jed.kaplan@jrc.it>
To: <GRASSLIST@baylor.edu>
Sent: Wednesday, March 09, 2005 4:26 PM
Subject: [GRASSLIST:6079] resampling to fractional cover

Hello,

I am using GRASS 6.0 cvs on Mac OS 10.3.

I have a very high-resolution raster map with category data. I want to
make a series of coarse resolution raster maps from this base map that
contain the fraction of each coarse-resolution grid cell that is occupied
by a particular category in the fine-resolution base map.

I have looked at r.average but don't really see how to approach this
problem (or even if it would be possible with GRASS).

Any advice or examples would be much appreciated.

Thanks for the help,

Jed Kaplan

3

On Wed, Mar 09, 2005 at 10:42:22PM +0100, Maciek Sieczka wrote:

Jed

You could write a script which would reduce your resolution by a given
factor (g.region res=... -p) and r.resamp'led your map in a loop.

... and/or combine this with r.clump and r.neighbors (size parameter).

Markus

Maciek

----- Original Message -----
From: "Jed O. Kaplan" <jed.kaplan@jrc.it>
To: <GRASSLIST@baylor.edu>
Sent: Wednesday, March 09, 2005 4:26 PM
Subject: [GRASSLIST:6079] resampling to fractional cover

>Hello,
>
>I am using GRASS 6.0 cvs on Mac OS 10.3.
>
>I have a very high-resolution raster map with category data. I want to
>make a series of coarse resolution raster maps from this base map that
>contain the fraction of each coarse-resolution grid cell that is occupied
>by a particular category in the fine-resolution base map.
>
>I have looked at r.average but don't really see how to approach this
>problem (or even if it would be possible with GRASS).
>
>Any advice or examples would be much appreciated.
>
>Thanks for the help,
>
>Jed Kaplan
>
>
>

--
Markus Neteler <neteler itc it> http://mpa.itc.it
ITC-irst - Centro per la Ricerca Scientifica e Tecnologica
MPBA - Predictive Models for Biol. & Environ. Data Analysis
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