[GRASSLIST:5663] Re: help with R

[Roger Bivand]

On Tue, 25 Feb 2003, Carlos Henrique Grohmann de Carvalho wrote:

> Hello all.
>  
> 
>  
> I need to do some statistical analysis of some morphological map I produced, 
> so I installed R and GRASS-R interface.
>  
> What I need should be simple: for each map (about six maps), I want general 
> stats (mean, quartiles, variance...), histogram, and them compare maps two 
> at a time with scatter plots and linear regression.
>  
> the problem is that I'm lost with R.
>  
> Does anyone know a simple tutorial, a step-by-step kind of thing, explanning 
> how to get the data from grass and them use it into R?
>  

A gentle guide for R itself from http://cran.r-project.org/other-docs.html
is: "A Guide for the Unwilling S User" by Patrick Burns, where S is a
general name for R or S-PLUS. There are plenty of others there. For 
getting the raster layers from GRASS to R, please see the help page of the 
interface function rast.get() - type help(rast.get) at the R prompt after 
loading the library with library(GRASS). There are plenty of examples on: 
http://grass.itc.it/statsgrass/grass_r_interface.html, and on its link to 
"Learning R".

Good luck!

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