def test_raise_compose_different_dim(self):
"""Test composing incompatible errors raises exception"""
error0 = QuantumError([np.diag([1, 1, 1,
-1])]) # 2-qubit coherent error
error1 = QuantumError([np.diag([1, -1])]) # 1-qubit coherent error
self.assertRaises(NoiseError, lambda: error0.compose(error1))
self.assertRaises(NoiseError, lambda: error1.compose(error0))
def test_compose_with_different_type_of_operator(self):
"""Test compose with Kraus operator."""
noise_x = QuantumError([((IGate(), [0]), 0.9), ((XGate(), [0]), 0.1)])
meas_kraus = Kraus([np.diag([1, 0]),
np.diag([0, 1])])
actual = noise_x.compose(meas_kraus)
expected = QuantumError([([(IGate(), [0]), (meas_kraus.to_instruction(), [0])], 0.9),
([(XGate(), [0]), (meas_kraus.to_instruction(), [0])], 0.1)])
self.assertEqual(actual, expected)
def test_compose_one_with_different_num_qubits(self):
"""Test compose errors with different number of qubits."""
noise_1q = QuantumError([((IGate(), [0]), 0.9), ((XGate(), [0]), 0.1)])
noise_2q = QuantumError([((IGate(), [0]), 0.8), ((XGate(), [1]), 0.2)])
actual = noise_1q.compose(noise_2q)
expected = QuantumError([([(IGate(), [0]), (IGate(), [0])], 0.9 * 0.8),
([(IGate(), [0]), (XGate(), [1])], 0.9 * 0.2),
([(XGate(), [0]), (IGate(), [0])], 0.1 * 0.8),
([(XGate(), [0]), (XGate(), [1])], 0.1 * 0.2)])
self.assertEqual(actual, expected)
def test_compose(self):
"""Test compose two quantum errors."""
noise_x = QuantumError([((IGate(), [0]), 0.9), ((XGate(), [0]), 0.1)])
noise_y = QuantumError([((IGate(), [0]), 0.8), ((YGate(), [0]), 0.2)])
actual = noise_x.compose(noise_y)
expected = QuantumError([([(IGate(), [0]), (IGate(), [0])], 0.9 * 0.8),
([(IGate(), [0]), (YGate(), [0])], 0.9 * 0.2),
([(XGate(), [0]), (IGate(), [0])], 0.1 * 0.8),
([(XGate(), [0]), (YGate(), [0])], 0.1 * 0.2)])
self.assertEqual(actual, expected)
def test_compose_both_unitary_standard_gates(self):
"""Test compose of two unitary standard gate errors"""
unitaries0 = self.mixed_unitary_error([0.9, 0.1], ['z', 's'])
unitaries1 = self.mixed_unitary_error([0.6, 0.4], ['x', 'y'])
error0 = QuantumError(unitaries0, standard_gates=True)
error1 = QuantumError(unitaries1, standard_gates=True)
error = error0.compose(error1)
target = SuperOp(Kraus(unitaries0)).compose(Kraus(unitaries1))
for j in range(4):
circ, _ = error.error_term(j)
self.assertIn(circ[0]['name'], ['s', 'x', 'y', 'z'])
self.assertEqual(circ[0]['qubits'], [0])
self.assertEqual(SuperOp(error), target)