It has never been really optimised, and I'm no professional programmer, but it still works a few tens times faster than any RPL program, and it handles several options as well. I have to admit, though, that it could possibly be a little faster, and surely somewhat smaller. An interesting feature of this program is that it can't crash. Apart from that, it works all right. By the way, here is PIX, from the same family as the one above, and from which the latter actually derives.
Options are strictly the same.