(notebook is attached)
The function I want to fit to is:
T == -((A2^2) /(1 + 4 (pos2 - w - P T)^2/k1^2))
The problem is that
func[A2_, k1_, pos2_, P_, w_] :=
T /. NSolve[T == -((A2^2)/(1 + 4 (pos2 - w - P T)^2/k1^2)), T, Reals][]];
func[A2, k1, pos2, P, 14000] /. startpar
leads to an error message. This is because NSolve does not recognize the the replacement command and therefore tries to solve the equation analytically. The same holds true when I use FindFit. Does anyone has an idea how to solve the problem?
Is there another way to fit implicit functions?
Thanks in advance for your help!!!
Attachment: fitimplicitfunc.nb, URL: ,