def test_mul_with_qOp_preserves_first_qOp_noise_model(self):
'''
Checks that after multiplication, the resulting `qOp` has
the same noise model as the first operand.
'''
op1 = qOp(kraus_ops=damping_map(0.3))
op2 = qOp()
np.testing.assert_array_equal((op1 * op2)._qOp__noise_model,
damping_map(0.3))
self.assertEqual((op2 * op1)._qOp__noise_model, None)
def test_set_noise_model(self):
'''
Verifies that setting a noise model succeeds.
'''
self.test_op.set_noise_model(damping_map(0.2))
some_op = qOp(np.eye(2), damping_map(0.2))
list_of_kraus_ops = [
np.array([[1, 0], [0, np.sqrt(0.8)]]),
np.array([[0, np.sqrt(0.2)], [0, 0]]),
]
np.testing.assert_array_equal(
some_op._qOp__noise_model.getKrausOperators(), list_of_kraus_ops)
np.testing.assert_array_equal(
self.test_op._qOp__noise_model.getKrausOperators(),
list_of_kraus_ops)
def test_qOpSizeMismatchWithNoiseModel(self):
'''
An exception gets thrown if the dimensions of the Kraus operators don't
match the dimensions of the ``qOp`` when calling
``qOp.set_noise_model()``.
'''
twoQubitOperator = qOp().kron(qOp())
self.assertRaises(WrongShapeError, twoQubitOperator.set_noise_model,
damping_map(0.5))
def test_apply_noisy_gate_with_raised_register(self):
'''
Deterministic verification of application of gate with
some NoiseModel set (using prob 1 amplitude damping) where
qReg needs to be raised.
'''
singleQubitInOneStateInitialy = qReg()
X.on(singleQubitInOneStateInitialy)
self.test_op.set_noise_model(damping_map(1.0))
self.test_op.on(singleQubitInOneStateInitialy, 1)
np.testing.assert_array_equal(
singleQubitInOneStateInitialy.dump_state(), [0, 1, 0, 0])
def test_apply_noisy_gate(self):
'''
Deterministic verification of application of gate with
some NoiseModel set (using prob 1 amplitude damping).
'''
registerInZeroStateInitially = qReg()
registerInOneStateInitially = qReg()
X.on(registerInOneStateInitially)
self.test_op.set_noise_model(damping_map(1.0))
self.test_op.on(registerInZeroStateInitially)
self.test_op.on(registerInOneStateInitially)
np.testing.assert_array_equal(
registerInZeroStateInitially.dump_state(), [1, 0])
np.testing.assert_array_equal(registerInOneStateInitially.dump_state(),
[1, 0])
# Prep a qReg in the |1> state
qubit = qReg()
X.on(qubit)
# Send it through an amp decay channel with 0.3 chance of decay.
if len(sys.argv) > 1 and int(sys.argv[1]) > 0:
n_runs = int(sys.argv[1])
else:
n_runs = 1000
if len(sys.argv) > 2 and float(sys.argv[2]) >= 0 and float(sys.argv[2]) <= 1:
prob = float(sys.argv[2])
else:
prob = 0.3
noisy_channel = qOp(kraus_ops=damping_map(prob))
zeros = 0
ones = 0
print("Sending the state |1> through a noisy channel {} times with amplitude decay probability={}...".format(n_runs, prob))
for i in range(n_runs):
noisy_channel.on(qubit)
result = qubit.measure(0)
if result == 0:
zeros += 1
# Reset qReg to |1> for next run.
X.on(qubit)
else:
# No need to reset qReg
ones += 1