Thanks for the help Mark. But what I am trying to accomplish is that when I input the known variables it calcs the rest, then based on that, I want to loop thru only width and depth (using the diam, volume, velocity and friction that was gathered) that way I only have to enter eitherwidth or depth not both (setq A(rnd_to_sqr diam B))
if I enter A (since I already know diam), this will calc the other side--then, if I can't use that size, I'll try another..