function [z] = cyl2cart(c,xi,yi,varargin)
% z=cyl2cart(c,xi,yi);
%
% Re-grids model output in cylindrical coords to cartesian.
%  c     is a 2-D or 3-D scalar or z-vector field
%  xi,yi are vectors of the new regular lat-lon grid to interpolate to.
%  z     is the interpolated data with dimensions of size(xi) by size(yi).
%  theta=0 is at 12 o'clock.
%
% e.g.
% >> t=rdmds('Ttave.0000513360');
% >> xi=-179:2:180;yi=-89:2:90;
% >> ti=cyl2cart(t,xi,yi);
%

NN=size(c);
[theta rho nz]=size(c);
[RHO,THETA] = meshgrid(1:rho,-pi+2*pi/theta:2*pi/theta:pi);
[x,y] = pol2cart(THETA,RHO);
nx=theta;ny=rho;

X=reshape(x,[1 nx*ny]);
Y=reshape(y,[1 nx*ny]);
del=griddata_preprocess(Y,X,yi,xi',varargin{:});

for k=1:nz;
 C=reshape(c(:,:,k),[1 nx*ny]);
z(:,:,k)=griddata(Y,X,C,yi,xi',varargin{:});
end % k

% Split vertical and time dimensions
if size(NN,2)>2
z=reshape(z,[size(z,1) size(z,2) NN(3:end)]);
end