I'm sorry if this is a simple question, but I haven't been able to figure it out on my own. If I have a set of data for several different variables is it possible to have mathematica find the simplest function of one variable in terms of the others that perfectly agrees with each trial in the data set? I'd much prefer if it satisfies each trial exactly rather than approximately (I understand that this could complicate the function significantly). I've been looking at nonlinearfit, but frankly don't have enough experience in mathematics to really understand all of the parameters. Thanks for bearing with me, I know that this question lacks a little in clarity but I hope that you get what I'm asking.