[GRASSLIST:5629] Re: histogram for compare two maps

[Roger Bivand]

On Fri, 21 Feb 2003, Carlos Henrique Grohmann de Carvalho wrote:

> I want to analyse some raster maps by making a histogram of 
>  
> "classes x frequency", and also check for linear relations between two or 
> more maps with scatter diagrams.
>  
> what would be the best way to do it ? I believe I have to reclass (or 
> something like that) both maps to the same number of categories, rigth?
>  
One possibility might be to use the interface between GRASS and R, which 
can provide the statistical graphics you would like. You would need to 
install R, though, and learn something of how you can use it to do this 
kind of thing. R is at http://cran.r-project.org/, more information on the 
interface at http://grass.itc.it/statsgrass/index.html

Roger

-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Breiviksveien 40, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 93 93
e-mail: Roger.Bivand at nhh.no