[GRASS-user] edit category information?

[Michael Barton]

On 9/6/07 4:57 AM, "Markus Neteler" <neteler at itc.it> wrote:

> Hamish wrote on 09/06/2007 12:45 PM:
>> Kirk Wythers wrote:
>>   
>>> I am looking to edit a raster map's category information.
>>>     
>> ..
>>   
>>> I would like to add category names (Oak, Pine, Spruce, etc...) to
>>> these numbers.I have been looking around for a way to do it
>>> (r.reclass?, r.recode?). I'm just not sure what is the "approved"
>>> approach here. Any suggestions?
>>>     
>> 
>> 
>> r.support will do it in interactive mode from the command line. That
>> uses the funny old esc-enter interface, but it works.
>> 
>> or edit the $MAPSET/cats/$MAPNAME file by hand, it's a simple text file.
>> Use one of the categorical spearfish maps as an example.
>>   
> How complicated would it be to develop an optional tcl frontend (like
> g.mapsets has) for
> r.support/cats editing? The format isn't that complicated (4 header
> lines, then ':' separated):
> 
> cat nc_spm_06/PERMANENT/cats/landuse96_28m
> # 24 categories
> South-West Wake county: NC Land Use 1996 clipped
> 
> 0.00 0.00 0.00 0.00
> 0:not classified
> 1:High Intensity Developed
> 2:Low Intensity Developed
> [...]
> 
> Markus
> 

The main thing needed first is a way to get category information INTO
r.support from a file and/or stdin. Basically, it needs a "rules" file
option like has been added to r.reclass and r.recode. If it had the same
syntax as r.reclass, it would simplify things from a user point of view. We
could then just use the same simple 'rules' interface to change categories
and labels on an existing map as we do to reclassify a map. e.g....

0 = 0 not classified
1 thru 2 = 1 developed


Michael


__________________________________________
Michael Barton, Professor of Anthropology
Director of Graduate Studies
School of Human Evolution & Social Change
Center for Social Dynamics and Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton