def test_is_classical_cov_squeezed():
""" Tests that a squeezed state is not classical"""
nbar = 1.0
phase = np.pi / 8
r = np.arcsinh(np.sqrt(nbar))
cov = TMS_cov(r, phase)
assert not is_classical_cov(cov)
def test_is_classical_cov_thermal(nbar):
""" Tests that a thermal state is classical"""
cov = (2 * nbar + 1) * np.identity(2)
assert is_classical_cov(cov)