[R-sig-Geo] [R] ascii-grid export

[Barry Rowlingson]

On Wed, Nov 6, 2013 at 6:43 PM, Enzo Cocca <enzo.ccc at gmail.com> wrote:
> hi Barry,
> thanks for your help.
>  Abaut the question why I want  to write a non-geographic
> coordinate-based  I answer that I don't  have my data in geographic
> coordinates but in local coordinates.
> So I want to export the map in local coordinate to overlap on my data

 But the variogram "map" can't overlap on your data! The value of the
variogram map at (x,y) is related to the covariance of data at
*spatial separation* x units apart horizontally and y units apart
vertically. Hence the variogram map is centred on 0,0, and the value
at (0,0) is the 'nugget' variance - the variance at distance zero.

 The local coordinates of your *data* may be in metres, but the axes
of the variogram map is strictly *separation in metres*.

I think further questions really need to go to R-sig-geo - I'm
diverting this there and I've taken r-help off the to: list - if
you're not a member of r-sig-geo then you should probably sign up now!

Barry