def roll(self):
    """ Calculates the Roll of the Quaternion. """

    x, y, z, w = self.x, self.y, self.z, self.w
    return math.atan2(2*y*w - 2*x*z, 1 - 2*y*y - 2*z*z)
def roll ( self ) : x , y , z , w = self . x , self . y , self . z , self . w return math . atan2 ( 2 * y * w - 2 * x * z , 1 - 2 * y * y - 2 * z * z )
Calculates the Roll of the Quaternion.