Summary: I'm having problems correctly entering my custom equation in the curve fit tool. Is there a better way?
I'm running MATLAB 7.1 (R14) Student Version with the Curve Fitting Toolbox version 1.1.4.
I'm trying to fit a custom equation to my data. Based on theoretical concerns, I expect the fit to involve a decaying exponential and a couple of error functions.
When I try to enter the custom equation in the "Create Custom Equations" editor, I apparently always screw up something because the resulting fit is a straight line. However, when I try coding the equation in an m-file, I can hand-adjust the parameters to get a reasonably good fit.
Is there a better way to enter custom equations? Is there some way I can take my m-file, or a modified version of it, and tell cftool to use that as the custom equation? Am I missing something obvious?