Is there an elegant way to do a bag diffeence between 2 arrays, rather than a set difference? [1,1,1,2,3,3,4,4,4] <something> [1,2,3,4,4] gives: [1,1,3,4] If ordering is preserved that would be great. The - operater removes duplicates, which is what I don't want. If it is staring me in the face, I can't spot it! Hugh