[GRASS-user] Some questions about DEMs

[Hamish]

Maciek wrote:
> For heterogenous input data I'd try the nn algorithm in
> nnbathy, through r.surf.nnbathy (http://grass.osgeo.org/wiki/Addons#r.surf.nnbathy).

It is great for sparse points, but for contour lines + hydrological
modeling it is not the best. See nn valley staircase effect in
 http://grass.osgeo.org/wiki/Contour_lines_to_DEM


regards,
Hamish