def test_x_y_from_zeta_eta():
zeta = np.random.rand(20) * 40
eta = np.random.rand(20)
x, y = x_y_from_zeta_eta(zeta, eta)
theta = np.pi * eta / 4.0
x_ = zeta * np.sin(theta)
y_ = zeta * np.cos(theta)
assert np.allclose(x, x_)
assert np.allclose(y, y_)
def test_extended_czjzek_polar():
S0 = {"zeta": 1, "eta": 0.1}
x, y = ExtCzjzekDistribution(S0, eps=0.05, polar=True).rvs(size=COUNT)
x1, y1 = x_y_from_zeta_eta(*x_y_to_zeta_eta(x, y))
np.testing.assert_almost_equal(x, x1)
np.testing.assert_almost_equal(y, y1)
def test_czjzek_polar():
x, y = CzjzekDistribution(sigma=0.5, polar=True).rvs(size=COUNT)
x1, y1 = x_y_from_zeta_eta(*x_y_to_zeta_eta(x, y))
np.testing.assert_almost_equal(x, x1)
np.testing.assert_almost_equal(y, y1)