REMNAN

Tightened code.
Changed:
if nargout == 1 & nargin ~= 1,
z = size(x1); z0 = size(y1);
if z ~= z0, y1 = y1'; end;
if z(1) > z(2), x1 = [x1,y1]; else, x1 = [x1;y1]'; end;
end;
To:
if nargout == 1 & nargin ~= 1, x1 = [x1(:) y1(:)]; end;