'standardize the random variable, i.e. subtract mean and whiten
Parameters
x : array-like, 1d or 2d
Data to be whitened, if 2d then each row contains an independent
sample of the multivariate random vector
Returns
np.dot(x - self.mean, self.cholsigmainv.T)
Notes
See Also
whiten : rescale random variable, standardize without subtracting mean.'

def standardize(self, x):

    return self.whiten((x - self.mean))
