[GRASS-user] Re: Shapefile to Surface

[Markus Metz]

On Mon, Jan 31, 2011 at 9:29 PM, leonidas <leonidas_liakos at yahoo.gr> wrote:
>
> Markus thank you!
> I used r.in.xyz according to your instructions.
>
> I set the region as follow:
> g.region -a res=150
>
> And then r.in.xyz to generate the surface.
> The points are not located in the center of the cells but on the upper left
> corner. Is that a feature or I made a mistake with the region settings?

The extents of the region need to be adjusted. Get the N,S,E,W bounds
of the vector points, add 75 m to N and E, substract 75 m from S and
W, use these with res=150, but without -a, to set the region. N - S
and E - W should be multiples of 150. The points should now fall into
the cell centers, granted that the vector points are really evenly
spaced.

Markus M