[GRASSLIST:2219] converting GRASS data for trend surface analysis in R

[Carlos Henrique Grohmann]

Hello all

I'm trying to do some trend surface analysis with GRASS data in R, but I with
some problems:

1 - when I get the raster from GRASS, surf.ls() doesn't accept it, since its not
in x,y,z format:

> str(isobase)
List of 1
 $ isobases.auto: num [1:241266] 771 770 769 768 767 ...
>

So, how can I change this to a format that surf.ls() understands?

2 - I'll try several degrees of surfaces, so I'll use surf.ls(), but what about
residuals? can I get them with residuals()?

thanks in advance

Carlos Grohmann

-- 
+-------------------------------------------------+
        Carlos Henrique Grohmann - Guano  
    Geologist - MSc Student at IGc-USP - Brazil
       Linux User #89721  ICQ: 214752832
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