Curve fitting real functions
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When doing my research to see how are real functions fitted in MATLAB, no answer has been found. Only the fitting of complex functions is proposed. Why is that?
Thanks in advance :^)
8 个评论
Rik
2020-12-10
What do you mean? I don't believe I have seen any complex function being fitted yet (although I don't doubt it is possible).
wallflower
2020-12-10
编辑：wallflower
2020-12-10
Rik
2020-12-10
I don't have that toolbox, so I can't comment on why that is only complex-valued.
I'm much more familiar with the standard fit function. Plenty of example of real-valued functions being fitted.
I suspect the answer to your why question is the domain: I would guess the function in RF analysis are simply complex-valued by design or convention.
wallflower
2020-12-10
Rik
2020-12-10
I don't understand what you want well enough to be able to help you.
wallflower
2020-12-10
riccardo
2020-12-10
The curve fitting tool seems to have the rational function as an option.
Alternatively, you could always revert to using "fzero" or "fminsearch", by converting your problem to minimising the residuals of:
<YourFunctionR>(f) * <denominator polynomial> - <numerator polynomial> = 0
wallflower
2021-1-4
采纳的回答
Steven Lord
2020-12-10
0 个投票
There is a collection of library models that can be used with functionality in Curve Fitting Toolbox. One type of model included in that collection is 'rational', which contains polynomials of degree up to 5 for both the numerator and denominator. If that's not sufficient, you can also create your own custom model.
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