Nonlinear Curve Fit Adding Custom Equation

[adv11]

I am relatively new to fitting data in LabVIEW, but I figured out fitting with premade functions fine (ex: linear, Gaussian, etc.). I need to fit data to a long, complicated equation now. Can anyone explain how to wire something to the Nonlinear Curve Fit VI that communicates what equation it should be using to fit? I have tried to find examples on here and on YouTube, but unfortunately there's still a little piece missing for me. 

Thank you in advance

[altenbach]

Start reading here, for example.

[adv11]

Thank you very much. I still am struggling with making my own because I cannot find where some of the functions come from. It seems like most examples have the applicable equation in a white box with a blue border (I'll attach a picture). I'm curious as to what exactly this is and how I can make my own. Thank you!

[altenbach]

This is a static VI reference containing the model for the function. Just double-click it to open the VI.

Note that it needs to be strictly typed, i.e. all terminals must match the template). Have you looked at the help? Start with the template, implement the model that calculates Y as a function of X and the parameters, then drop it into a static reference. Right-click to make the reference strictly typed.