Q: s.surf.idw

Grass package grass at sun1
Wed Dec 18 12:06:16 EST 1996

Andreas, just multiply your values by 10. Your version of grass
apparently doesn't support floating point results yet, so s.surf.idw
truncates the results of the calculation into integers... Also look
at the man pages for r.mapcalc for ways around this problem!


> We do have a site-list of field measurements
> (soil resistivity) which we interpolate to
> raster by means of s.surf.idw.
> Z-values in the site-list are floating-point
> ranging from 0.0 to 25.0.
> The output of s.surf.idw creates a raster map with
> only five categories. 
> I need at least 255 categories, how can this be
> accomplished ?
> Do I have to build categories outside grass, i.e.
> create the site-list with categories for Z-values 
> instead of using original (measured) data ??
> Thanks for your help,
> Andreas
> Dept. of Geophysics
> Univ. of Bremen

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