def test_alpha():
assert_equal(1.0 / xs.k, xs.alpha(0.0, 1.0, 0.0, xs.m_n, 1.0))
assert_almost_equal(1.0, (1.0 / (12.0*xs.k)) / xs.alpha(0.0, 1.0, 0.0, 12*xs.m_n, 1.0))
assert_almost_equal(1.0, (1.5 / (12.0*xs.k)) / xs.alpha(0.5, 1.0, np.pi/2, 12*xs.m_n, 1.0))
assert_almost_equal(1.0, (1.5 / (12.0*xs.k*2.0)) / xs.alpha(0.5, 1.0, np.pi/2, 12*xs.m_n, 2.0))
assert_almost_equal(1.0, ((1.5 - 2*np.sqrt(0.5)*np.cos(np.pi/4)) / (12.0*xs.k*2.0)) / xs.alpha(0.5, 1.0, np.pi/4, 12*xs.m_n, 2.0))
def test_alpha_given_theta_pi():
E_prime = np.linspace(0.5, 1.5, 101)
E = np.linspace(0.75, 1.25, 101)
M_A = np.linspace(1, 300, 101)
T = np.linspace(1, 1800, 101)
assert_array_almost_equal(xs.alpha_given_theta_pi(E_prime, 1.0, 12*xs.m_n, 2.0), xs.alpha(E_prime, 1.0, np.pi, 12*xs.m_n, 2.0))
assert_array_almost_equal(xs.alpha_given_theta_pi(E_prime, E, 12*xs.m_n, 2.0), xs.alpha(E_prime, E, np.pi, 12*xs.m_n, 2.0))
assert_array_almost_equal(xs.alpha_given_theta_pi(E_prime, E, M_A, 2.0), xs.alpha(E_prime, E, np.pi, M_A, 2.0))
assert_array_almost_equal(xs.alpha_given_theta_pi(E_prime, E, M_A, T), xs.alpha(E_prime, E, np.pi, M_A, T))
