function [dA1dA2] = f_union(dA1,dA2)

%UNION:  The union of matrix of fuzzy values A and B over the same
% 	 universe will be calculated. 
%
%                              [A1&A2] = UNION(A1,A2)
%
%        Matrices A and B are matrices of membership functions. Output of 
%        this  function is result grade of membership function A1&A2 over 
%        the same universe.
%                                           See also INTERSEC and COMPLE.

% FISMAT: Fuzzy Inference Systems toolbox for MATLAB
% (c) A. Lotfi, University of Queensland (Email: lotfia@s1.elec.uq.oz.au)
% 13-10-93
% The program has been tested on MATLAB version 4.1, Sun workstation.

if size(dA1) ~= size(dA2)
	error('Two fuzzy sets DA1 ana DA2 must be the same dimension')
end

if (max(max(dA1)) > 1) | (max(max(dA2)) > 1) | (min(min(dA1)) < 0) | (min(min(dA2)) < 0)
	error('Grade of membership function should not be more than one or less than zero.')
end

dA1dA2=max(dA1,dA2);