how to calculate the frequency features of eeg brain signals?

What code should I use to calculate the frequency features : Spectral Centroid, Variational Coefficient and Spectral Skew from eeg brain signals?

[Sudhakar Shinde]

For Spectral Centroid:

https://www.mathworks.com/help/audio/ref/spectralcentroid.html

Spectral Skew:

https://www.mathworks.com/help/audio/ref/spectralskewness.html

[leyi gachi]

Do I need to get fft from the signal first?

[KSSV]

You should use fft first.

[leyi gachi]

I have to calculate the psd first and then extract the frequency features. Do I have to get the fft signal before calculating the psd?