[GRASS-user] dems from coordinate lists

[Hamish]

Micha wrote:
> From my understanding, r.in.xyz is best suited for cases
> where you have a very high density of x-y values (i.e. lidar
> data) and you want to create a raster where each cell will
> contain several  of the original points. You can then
> choose to average all point values (or max, min, etc) to
> create the final cell value.

r.in.xyz is also good if your input data coords are already in a
grid, as if you set the region bounds correctly it can replicate
that grid and therefore the input data *exactly*.


> 1- You want the final raster at the same or larger
> resolution as the original points, and

ie r.in.xyz and r.resamp.stats are good at aggregating data,
v.surf.rst and r.resamp.interp are good at interpolating data.


> 2- You have at least one point value for *every* target
> raster cell. (Other wise you'll end up with cells with value
> '0')

only for the "n" count map (which is great for checking that
r.in.xyz is doing what you meant). for other methods cells with
no-data are filled with NULL, not 0. (as you might hope for
something like minimum!)


regards,
Hamish