How to interpolate an elevation raster from vector data set?

[Malcolm Williamson]

Hello, Andreas
> 
> 	I digitized a topographic map (scale 1:25000) to get a vector
> 	data set with contours, representing the elevation.
> 
> 	How to interpolate the vector data set to generate a raster
> 	data set representing the elevation information?
> 
s.surf.tps offers the most control over such interpolations. Use v.to.rast to
convert your contour lines to raster at an appropriate resolution (20m ?), then
use r.stats -1zg input=raster_file_name | s.in.ascii sites=new_sitesfile_name .
We found it helpful to thin out the raster data a little with r.random; we ended
up using 30% of the original raster cells to get good results. The unused cells
can be used to check the interpolated output.

You could also get your hands on a pre-alpha (?) version of v.surf.tps from
irena at zorro.cecer.army.mil (hope that's the correct address!). No documentation
on this one yet!

Regards,
-- 
Malcolm D. Williamson - Research Assistant       E-mail: malcolm at cast.uark.edu
Center for Advanced Spatial Technologies      Telephone: (501) 575-6159
Ozark Rm. 12                                        Fax: (501) 575-3846 
University of Arkansas              
Fayetteville, AR 72701