% MESHGRID MESHGRID Generate Grid Mesh For Plots
% 
% Usage
% 
% The meshgrid function generates arrays that can be used for the
% generation of surface plots.  The syntax is one of 
% 
%   [X,Y] = meshgrid(x)
%   [X,Y] = meshgrid(x,y)
%   [X,Y,Z] = meshgrid(x,y,z)
% 
% where x,y,z are vectors, and X,Y,Z are matrices.  In the first
% case [X,Y] = meshgrid(x), the rows of X and the columns of Y
% contain copies of the vector x.  In the second case 
% [X,Y] = meshgrid(x,y), the rows of X contain copies of x, and
% the columns of Y contain copies of y.  In the third case, each
% input is copied along the row, column or slice direction of the
% corresponding output variable.
function [X,Y,Z] = meshgrid(x,y,z)
  if (nargin == 0)
    error('meshgrid requires at least one input argument');
  end
  if (nargin == 1)
    X = repmat(x(:)',[numel(x),1]);
    Y = X';
  elseif (nargout == 2)
    X = repmat(x(:)',[numel(y),1]);
    Y = repmat(y(:),[1,numel(x)]);
  else
    X = repmat(x(:)',[numel(y),1,numel(z)]);
    Y = repmat(y(:),[1,numel(x),numel(z)]);
    Z = repmat(reshape(z,[1,1,numel(z)]),[numel(y),numel(x),1]);
  end