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