Curve fitting of harmonic oscillators

I'm attempting to fit experimental parametric oscillatory data to ellipses and other parametric equations. Would such a task need to be manually coded, or is there a routine already present in IGOR?

I've attached an example plot that I want to fit.
oscillator.pxp (57.28 KB)
While I haven't used it myself, I believe support for parametric functions is included in Igor. Try executing DisplayHelpTopic "Fitting Implicit Functions" for more information.
741 wrote:
While I haven't used it myself, I believe support for parametric functions is included in Igor. Try executing DisplayHelpTopic "Fitting Implicit Functions" for more information.


Yes, this is just what I'm looking for. Thank you.