[R-sig-Geo] Linear interp irregular samples to irregular points

[Tim Keitt]

Tps() is great -- I've been using it. I suppose I could use it for
this problem too by setting the curvature penalty to zero (forcing it
to interpolate). The interpp a la Miha suggestion I think will be
better for what I want.

THK

On 6/5/07, Roger Bivand <Roger.Bivand at nhh.no> wrote:
> On Tue, 5 Jun 2007, Tim Keitt wrote:
>
> > Anyone know of code that will do bilinear interpolation from irregular
> > samples to another set of irregular locations (including points
> > possibly outside the convex hull of the original points)? Akima
> > interpolates to a regular grid AFAICT. I did find one package on CRAN
> > that does this will splines, but I want something simpler. (The
> > particular application requires many repeated calls.)
>
> Would Tps() and predict() for Tps objects in fields meet your needs? I've
> used it for "faking" LOO CV to match spline interpolation to gstat.cv() in
> gstat, and it doesn't complain on many calls.
>
> Roger
>
> >
> > THK
> >
> >
>
> --
> Roger Bivand
> Economic Geography Section, Department of Economics, Norwegian School of
> Economics and Business Administration, Helleveien 30, N-5045 Bergen,
> Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
> e-mail: Roger.Bivand at nhh.no
>
>


-- 
Timothy H. Keitt, University of Texas at Austin
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