def test_save_expval_var_cptp_pauli(self, pauli):
"""Test Pauli expval_var for stabilizer circuit"""
SUPPORTED_METHODS = [
'density_matrix', 'density_matrix_gpu', 'density_matrix_thrust'
]
SEED = 5832
opts = self.BACKEND_OPTS.copy()
if opts.get('method') in SUPPORTED_METHODS:
oper = qi.Pauli(pauli)
# CPTP channel test circuit
channel = qi.random_quantum_channel(4, seed=SEED)
state_circ = QuantumCircuit(2)
state_circ.append(channel, range(2))
state = qi.DensityMatrix(state_circ)
expval = state.expectation_value(oper).real
variance = state.expectation_value(oper**2).real - expval**2
target = [expval, variance]
# Snapshot circuit
circ = transpile(state_circ, self.SIMULATOR)
circ.save_expectation_value_variance(oper, [0, 1], label='expval')
qobj = assemble(circ)
result = self.SIMULATOR.run(qobj, **opts).result()
self.assertTrue(result.success)
value = result.data(0)['expval']
self.assertTrue(allclose(value, target))
def test_roundtrip_quantum_channel(self, rep):
"""Test round-trip serialization of a DensityMatrix"""
chan_cls = {
"Choi": qi.Choi,
"SuperOp": qi.SuperOp,
"Kraus": qi.Kraus,
"Stinespring": qi.Stinespring,
"PTM": qi.PTM,
"Chi": qi.Chi,
}
obj = chan_cls[rep](qi.random_quantum_channel(2, seed=10))
self.assertRoundTripSerializable(obj)
def test_save_expval_var_cptp_pauli(self, method, device, pauli):
"""Test Pauli expval_var for stabilizer circuit"""
SEED = 5832
oper = qi.Operator(qi.Operator(qi.Pauli(pauli)))
channel = qi.random_quantum_channel(4, seed=SEED)
circ = QuantumCircuit(2)
circ.append(channel, range(2))
qubits = [0, 1]
self._test_save_expval(circ,
oper,
qubits,
True,
method=method,
device=device)
def test_set_superop(self, method, device, num_qubits):
"""Test SetSuperOp instruction"""
backend = self.backend(method=method, device=device)
seed = 100
label = 'state'
target = qi.SuperOp(qi.random_quantum_channel(2**num_qubits,
seed=seed))
circ = QuantumCircuit(num_qubits)
circ.set_superop(target)
circ.save_superop(label=label)
# Run
result = backend.run(transpile(circ, backend, optimization_level=0),
shots=1).result()
self.assertTrue(result.success)
simdata = result.data(0)
self.assertIn(label, simdata)
value = qi.SuperOp(simdata[label])
self.assertEqual(value, target)
def test_superop_linop(self):
orig = qi.SuperOp(qi.random_quantum_channel(4, seed=10))
compat = cqi.SuperOp(orig.data)
self.assertEqual(2 * compat - orig, orig)
self.assertEqual(2 * orig - compat, orig)
def test_superop_eq(self):
orig = qi.SuperOp(qi.random_quantum_channel(4, seed=10))
compat = cqi.SuperOp(orig.data)
self.assertEqual(compat, orig)
self.assertEqual(orig, compat)
