How to curve fit an equation with sigma function
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Dear all,
I would like to get coefficient C0, C1....CN from the below equation,
![function.JPG](https://www.mathworks.com/matlabcentral/answers/uploaded_files/231322/function.jpeg)
I have enclosed herewith an excel having x and y co-ordinates.
Can anybody please let me know how to write this equation in 'custom equation' option in curve fitting tool or is there any other way to do it?
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Catalytic
2019-7-27
C = polyfit( sqrt( x.^2+y.^2) , Z, N)
4 个评论
Matt J
2019-7-29
编辑:Matt J
2019-7-29
As you mentioned as its a higher order polynomial I will not use polyfit due to higher perecentage error.
No, that is not what I said. What I said was "It's not that polyfit is better or worse at fitting high order polynomials. It's just that high order polynomials are typically a bad thing...".
Stop using high order polynomials. Use splines instead.
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