Thank you, I just found an example with modulo right before I got your email On Mon, 11 May 2009 12:44:39 -0700, "Bill Schottstaedt" <bil at ccrma.Stanford.EDU> wrote: > s7 is scheme, not common lisp -- you want modulo > and remainder, not mod and rem. > > (/ 7 4) or whatever is supposed to return a fraction, > even in CL.