def phi_gamma_ellipticity(phi, gamma):
    """

    :param phi: angel
    :param gamma: ellipticity
    :return:
    """
    e1 = gamma*np.cos(2*phi)
    e2 = gamma*np.sin(2*phi)
    return e1, e2
def phi_gamma_ellipticity ( phi , gamma ) : e1 = gamma * np . cos ( 2 * phi ) e2 = gamma * np . sin ( 2 * phi ) return e1 , e2
:param phi: angel
    :param gamma: ellipticity
    :return: