def center_and_norm(x, axis=(-1)):
 x = np.rollaxis(x, axis)
 x -= x.mean(axis=0)
 x /= x.std(axis=0)

def center_and_norm ( x , axis = ( - 1 ) ) : x = np . rollaxis ( x , axis ) x -= x . mean ( axis = 0 ) x /= x . std ( axis = 0 )
centers and norms x **in place** parameters x: ndarray array with an axis of observations measured on random variables .