def test_tensor(self):
"""Test tensor method."""
rho0, rho1 = np.diag([1, 0]), np.diag([0, 1])
rho_init = DensityMatrix(np.kron(rho0, rho0))
chan1 = Stinespring(self.UI)
chan2 = Stinespring(self.UX)
# X \otimes I
chan = chan2.tensor(chan1)
rho_targ = DensityMatrix(np.kron(rho1, rho0))
self.assertEqual(chan.dim, (4, 4))
self.assertEqual(rho_init.evolve(chan), rho_targ)
# I \otimes X
chan = chan1.tensor(chan2)
rho_targ = DensityMatrix(np.kron(rho0, rho1))
self.assertEqual(chan.dim, (4, 4))
self.assertEqual(rho_init.evolve(chan), rho_targ)
# Completely depolarizing
chan_dep = Stinespring(self.depol_stine(1))
chan = chan_dep.tensor(chan_dep)
rho_targ = DensityMatrix(np.diag([1, 1, 1, 1]) / 4)
self.assertEqual(chan.dim, (4, 4))
self.assertEqual(rho_init.evolve(chan), rho_targ)
def test_tensor(self):
"""Test tensor method."""
rho0, rho1 = np.diag([1, 0]), np.diag([0, 1])
rho_init = np.kron(rho0, rho0)
chan1 = Stinespring(self.matI)
chan2 = Stinespring(self.matX)
# X \otimes I
chan = chan2.tensor(chan1)
rho_targ = np.kron(rho1, rho0)
self.assertEqual(chan.dims, (4, 4))
self.assertAllClose(chan._evolve(rho_init), rho_targ)
# I \otimes X
chan = chan1.tensor(chan2)
rho_targ = np.kron(rho0, rho1)
self.assertEqual(chan.dims, (4, 4))
self.assertAllClose(chan._evolve(rho_init), rho_targ)
# Completely depolarizing
chan_dep = Stinespring(self.depol_stine(1))
chan = chan_dep.tensor(chan_dep)
rho_targ = np.diag([1, 1, 1, 1]) / 4
self.assertEqual(chan.dims, (4, 4))
self.assertAllClose(chan._evolve(rho_init), rho_targ)
