gauss-newton algorithm residual bigger than matlab code

[Yvaine]

Hello,
Thank you for providing C++ implement of gauss-newton algorithm.But I have used the same data on cppopt::gaussNewton and lsqcurvefit of matlab(use guass newton also), the result is not the same, and the square residual of cppopt::gaussNewton is bigger than lsqcurvefit of matlab. Do you know the reason.

Thank you very much.

[bihuchao]

@Yvaine Can I have your original example code piece of CPPOPT & Matlab, I want to make it out.
Thank you!