Re: [GRASS-user] Re: XYZ Data (UTM32N) workflow to DEM and reprojection to Gauß Krüger 3

[Hamish]

Hi,

just to add to what others have already said; it is better to
reproject to your target projection _before_ doing the
rasterization step, that way you avoid the generational loss
from r.proj. Try to import them directly as points into your
target location.

So methods could be:

xyz.txt -> v.in.ascii -> v.proj -> v.surf.rst
 (for many millions of input points use the v.in.ascii -zbt flags)

or

xyz.txt -> m.proj (or cs2cs) -> r.in.xyz -> r.surf.nnbathy (addon)


r.in.xyz is very good at creating DEM cells at points with known
data, but it does not do any interpolation, you need the
r.surf.nnbathy module (or another r.surf.* or v.surf.* module)
to fill in the gaps.


good luck,
Hamish