Curve fitting using custom model
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Given set of x and y, how can I solve the parameter a, b and c in the model
y = a * x^b + c
to best fit the given data?
As I will further implement the algorithm in C++, I would prefer not using built-in Matlab functions to solve parameters.
Could anyone please suggest an algorithm? Many thanks, Kyle.
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Accepted Answer
Walter Roberson
on 28 Jul 2015
G = @(abc) sum((abc(1)*x0.^abc(2)+abc(3)-y0).^2);
ABC = fminsearch(G, [rand,rand,rand], 'MaxIters', 10000)
the result will not necessarily be exactly correct, and you can pass ABC back in instead of [rand,rand,rand], but I did find that with my test sometimes it cycled near the answer.
fminsearch is a gradient descent method.
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