[R] bivariate linear interpolation

[Andrew Robinson]

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Andrew

On Wed, May 04, 2011 at 12:52:03PM +0000, Halldór Björnsson wrote:
> Hi,
> 
> I have three matrices (X,Y,P) with the same dimension. The X,Y grid is
> regular and I want to
> perform linear interpolation to pick out certain points. In matlab
> appropriate call is
> something like
> 
> Pout=interp2(X,Y,P,Xout,Yout, method="linear")
> 
> where Xout and Yout are the locations where I want the Pout data
> (typically a different grid).
> (Scipy has this routine in interpolate.interp2d, with similar arguments)
> 
> 
> In R there is (as often) the choice between many different
> interpolation routines. Akima has one for irregularly spaced
> data (and does not like co-linearity in the data). Fields has another
> one, with a more complicated arguments.
> 
> What is the best R function that accomplishes this?
> 
> Sincerely
> Halldór
> 
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