labels<-->category# ???

[Malcolm Williamson]

> 
> We have obtained 7.5 min vector soil maps where the labels are
> meaningful but the category numbers vary as a function of the
> quad map.  Thus v.to.rast gives meaningless category numbers
> with meaningful labels.  How do I combine these maps into one
> complete soil map for the county? V.patch and r.mapcalc work on
> the category number and more or less ignore the labels. Is there
> a slick way to make the labels the category # in either vector
> or raster formats?
> 
> 
> Bruce Wylie
> 
The easiest way that I can think of is to use r.mapcalc with the "@" operator,
which looks at the category contents instead of the category value. For example:

>newmap = @oldmap

The GRASS4.1 manual notes that "...the category label must start with a valid 
number. Missing labels, or labels that do not start with a number will 
(silently) produce a 0 value for that category."

-- 
Malcolm D. Williamson - Research Assistant       E-mail: malcolm at cast.uark.edu
Center for Advanced Spatial Technologies      Telephone: (501) 575-6159
Ozark Rm. 12                                        Fax: (501) 575-3846 
University of Arkansas              
Fayetteville, AR 72701