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Hello Everyone,
I hope my email finds everyone in good health. Can anyone please help me how to actually find the interpolation function when I use the command "interp". I have attached a file that interpolates frequency based on phase angles and I have plotted the graph. But I would like to what is the equation that I have used here using "interp" and "cspline".
Thank you,
Faisal
You must first determine what shape of function you expect, and then choose the right fitting function.
I could imagine that in your case a linear fit is the best, that makes it a lot simpler.
You function would be y=a*x+b.
Mathcads functions to find a and b are slope() and intercept() respectively.
Luc
But I would like to what is the equation that I have used here using "interp" and "cspline".
Using cubic spline interpolation does not give you one function but a series of cubics which join smoothly.
For the theory behind it you may have a look at Spline interpolation - Wikipedia
If you need an analytic expression for one function you would better not use an interpolation but rather a regression, a curve fit.There are numerous ways to do so in Mathcad and you would have to decide at first which type of function to use for the fit.