matthiasm@8: function C = mysetdiff(A,B)
matthiasm@8: % MYSETDIFF Set difference of two sets of positive integers (much faster than built-in setdiff)
matthiasm@8: % C = mysetdiff(A,B)
matthiasm@8: % C = A \ B = { things in A that are not in B }
matthiasm@8: %
matthiasm@8: % Original by Kevin Murphy, modified by Leon Peshkin
matthiasm@8: 
matthiasm@8: if isempty(A)
matthiasm@8:     C = [];
matthiasm@8:     return;
matthiasm@8: elseif isempty(B)
matthiasm@8:     C = A;
matthiasm@8:     return; 
matthiasm@8: else % both non-empty
matthiasm@8:     bits = zeros(1, max(max(A), max(B)));
matthiasm@8:     bits(A) = 1;
matthiasm@8:     bits(B) = 0;
matthiasm@8:     C = A(logical(bits(A)));
matthiasm@8: end