def test_dot(self):
"""Test dot 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_y.dot(noise_x) # reversed order of compose
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_dot_both_unitary_standard_gates(self):
"""Test dot 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.dot(error1)
target = SuperOp(Kraus(unitaries0)).dot(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)