Gaussian interpolation with successive corrections

Code for Gaussian Interpolation with successive corrections

Code for Gaussian Interpolation with successive corrections. Running of the code is a little slow , but the results seem not bad. In this code I applied just one step successive corrections. The figure shows the Sea Level Pressure field from NCEP data. I used it to verify the interpolation results.
%------ Input: 'x' is the original longitude, 'y' is the original latitude -------
%--------- 'z' is the original data field,'rr' is the radius influence ------------
%------ 'xi' is the interpolate longitude, 'yi' is the interpolate latitude -------
%----------------------------------------------------------------------------------------
%------ Output: 'F'(interpolate value with successive corrections) --------
%------ 'F0'(interpolate value without successive corrections) --------
%------ 'FD'(interpolate value error for new grids) --------
%------ Notice: 'x,y,z' must be the same size, ------------
%------ the unit of input radius‘rr’is (m) -------
%----------------------------------------------------------------------------------------
% Usage: [x,y] = meshgrid(long,lati);
% [F F0 FD] = gaussian_interpolation(x,y,z,400*10^3,llon,llat);