Hi I have a long procedure, which calculates the potential of a physical system. The procedure returns something having the form Code (Text): potential = 1/(constant + z) where z is a variable. Now, I need to evaluate potential at different z. I can of course do something like Code (Text): z = 1; potential z=2; potential and so on, but is there a better way to do this without having to rewrite the procedure? I'm thinking about having something like potential[z], but that is perhaps too late for me to use this, without having to rewrite the whole thing? Thanks for any help. Best, Niles.