[GRASS-user] Interpolation on a Grid

[Hamish]

> > Frank Aragona wrote:
> >> I'd like to do an interpolation of xyz data points that
> >> I have, and put the interpolated data on 100' x 100'
> >> grid.  So that each 100' x 100' square has an
> >> associated elevation value.  Any suggestions as to how best
> >> to do this?

Hamish:
> > depending on how many input points you have either:
> >   v.in.ascii, g.region res=100, v.surf.rst
> > 
> > or for massive datasets (>1-3 million points):
> >   g.region res=100, r.in.xyz, r.to.vect, v.surf.rst
> > 
> > 
> > choice of method and {r|v}.surf.* interpolation module are subject to
> > nature of data & personal preference. see also r.surf.nnbathy in wiki
> > addons. the modules' manual pages should help you decide.

Frank wrote:
> But I'd like the interpolated surface to be a set of
> 100' x 100' vector grids, each 100 x 100 square with
> a discrete elevation value.  Is this possible?


after import & binning as a raster use v.mkgrid to make your 100x100 grid,
then use v.what.rast or v.rast.stats to give each square an elevation
value. or maybe r.to.vect is easier?


Hamish