PCA Covariance Matix

#1

How covariance matrix is got by np.dot(X_.T ,X_).
Why dot product is giving covariance?

#2

hey @aditrisriv ,
Mentor has done it correctly.

To understand it ,
actually the method to calculate covariance is
np.dot((x-mean_of_x),(x-mean_of_x).T)/(shape[0]-1)

But the mentor has already standardized the data , which means , X has already become , X-X.mean()

hence , on just calling the np.dot() function on X and X.T , it works and provides the correct cvariance matrix we actually needed.

I hope this helps.

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#3

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