Alberto wrote:
I had the same problem. As Hamish told me some weeks ago,
"r.surf.idw and r.surf.idw2 only produce CELL (integer)
maps."I solved my problem multiplying the input raster by 100
(r_bio in your case), then I interpolated with r.surf.idw
and finally divided once again by 100.
[depending on your needs] r.to.vect + v.surf.rst or r.surf.nnbathy
(from wiki addons) will create a /much/ nicer surface than IDW
methods. this explains why r.surf.idw module development is rather
neglected.
see also R-stats/grass interface kriging tools and v.surf.idw.
I am not sure if v.surf.idw handles floating-point data or just
integers, but as a total guess I'd say it would create FP output
due to the vector modules generally being more recently written.
Hamish