[R-sig-Geo] trend surface analysis

[Carlos Henrique Grohmann]

Hello,

What is the better way to perform trend surface analysis in R (with GRASS data),
with third-order surfaces (or higher levels?)

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