A couple of corrections perhaps.

This could just be an inconstancy in the documentation but here goes.

The functions xtract_spectral_inharmonicity and xtract_odd_even_ratio were both using the dft bin number as the order of the partial / harmonic in their calculations.

If you use the output of xtract_peak_spectrum / xtract_harmonic_spectrum as the input, this is not valid.

I have made some changes to the functions accordingly.

I had to change the interface to xtract_odd_even_ratio. It now considers all elements of the output of xtract_harmonic_spectrum, and you have to pass in the fundamental frequency. There may have been a cleaner way of doing this.