Nonlinear fit in MATLAB

Hello all,

I am trying to fit a function with one data set to another data set. I'm performing a nonlinear fit similar to something as follows:

y = c1.*x.^c2 

where y and x are two column vectors, and I am trying to solve for c1 and c2. Although it's a pretty straightforward answer, I thought some guidance from the community would be best in this matter as I've little experience with the nonlinear fitting capabilities of MATLAB.

Cheers

[Walter Roberson]

Take the log of both sides to make it a linear fit that polyfit can handle.

[Bjorn Gustavsson]

And if Walter's solution is not good enough, due to how noise in y is modified with the log, then use that solution to look for a minimization of

f = @(p,x,y) sum((y-p(1)*x.^p(2)).^2)

You can do that with fminsearc or, with minor modifications, lsqnonlin

[Cole Butler]

Thank you both for the suggestions!