def test_depolarizing() -> None:
p = 1.0 - np.exp(-1 / 20)
chan = qf.Depolarizing(p, 0).aschannel()
rho0 = qf.Density([[0.5, 0], [0, 0.5]])
assert qf.densities_close(rho0, chan.evolve(rho0))
rho0 = qf.random_density(1)
rho1 = chan.evolve(rho0)
pr0 = np.real(qf.purity(rho0))
pr1 = np.real(qf.purity(rho1))
assert pr0 > pr1
# Test data extracted from refereneqvm
rho2 = qf.Density([[0.43328691, 0.48979689], [0.48979689, 0.56671309]])
rho_test = qf.Density(
[[0.43762509 + 0.0j, 0.45794666 + 0.0j], [0.45794666 + 0.0j, 0.56237491 + 0.0j]]
)
assert qf.densities_close(chan.evolve(rho2), rho_test)
ket0 = qf.random_state(1)
qf.Depolarizing(p, 0).run(ket0)
rho1b = qf.Depolarizing(p, 0).evolve(rho0)
assert qf.densities_close(rho1, rho1b)
def test_kraus_complete():
kraus = qf.Kraus([qf.X(1)])
assert qf.kraus_iscomplete(kraus)
kraus = qf.Damping(0.1, 0)
assert qf.kraus_iscomplete(kraus)
assert qf.kraus_iscomplete(qf.Damping(0.1, 0))
assert qf.kraus_iscomplete(qf.Dephasing(0.1, 0))
assert qf.kraus_iscomplete(qf.Depolarizing(0.1, 0))
def test_askraus():
def _roundtrip(kraus):
assert qf.kraus_iscomplete(kraus)
chan0 = kraus.aschannel()
kraus1 = qf.channel_to_kraus(chan0)
assert qf.kraus_iscomplete(kraus1)
chan1 = kraus1.aschannel()
assert qf.channels_close(chan0, chan1)
p = 1 - np.exp(-50 / 15000)
_roundtrip(qf.Kraus([qf.X(1)]))
_roundtrip(qf.Damping(p, 0))
_roundtrip(qf.Depolarizing(0.9, 1))
def test_stdchannels_creation():
qf.Damping(0.1, 0).aschannel()
qf.Depolarizing(0.1, 0).aschannel()
qf.Dephasing(0.1, 0).aschannel()
def test_stdkraus_creation():
qf.Damping(0.1, 0)
qf.Depolarizing(0.1, 0)
qf.Dephasing(0.1, 0)