def _skew(data):
 data = np.ravel(data)
 mu = data.mean()
 m2 = ((data - mu) ** 2).mean()
 m3 = ((data - mu) ** 3).mean()
 return (m3 / np.power(m2, 1.5))

def _skew ( data ) : data = np . ravel ( data ) mu = data . mean ( ) m2 = ( ( data - mu ) ** 2 ) . mean ( ) m3 = ( ( data - mu ) ** 3 ) . mean ( ) return ( m3 / np . power ( m2 , 1.5 ) )
skew is third central moment / variance** .