def test_chc_vscf(self):
""" chc vscf test """
co2_2modes_2modals_2body = [
[[[[0, 0, 0]], 320.8467332810141], [[[0, 1, 1]],
1760.878530705873],
[[[1, 0, 0]], 342.8218290247543], [[[1, 1, 1]],
1032.396323618631]],
[[[[0, 0, 0], [1, 0, 0]], -57.34003649795117],
[[[0, 0, 1], [1, 0, 0]], -56.33205925807966],
[[[0, 1, 0], [1, 0, 0]], -56.33205925807966],
[[[0, 1, 1], [1, 0, 0]], -60.13032761856809],
[[[0, 0, 0], [1, 0, 1]], -65.09576309934431],
[[[0, 0, 1], [1, 0, 1]], -62.2363839133389],
[[[0, 1, 0], [1, 0, 1]], -62.2363839133389],
[[[0, 1, 1], [1, 0, 1]], -121.5533969109279],
[[[0, 0, 0], [1, 1, 0]], -65.09576309934431],
[[[0, 0, 1], [1, 1, 0]], -62.2363839133389],
[[[0, 1, 0], [1, 1, 0]], -62.2363839133389],
[[[0, 1, 1], [1, 1, 0]], -121.5533969109279],
[[[0, 0, 0], [1, 1, 1]], -170.744837386338],
[[[0, 0, 1], [1, 1, 1]], -167.7433236025723],
[[[0, 1, 0], [1, 1, 1]], -167.7433236025723],
[[[0, 1, 1], [1, 1, 1]], -179.0536532281924]]
]
num_modes = 2
num_modals = [2, 2]
vibrational_op_labels = _create_labels(co2_2modes_2modals_2body)
vibr_op = VibrationalOp(vibrational_op_labels, num_modes, num_modals)
converter = QubitConverter(DirectMapper())
qubit_op = converter.convert_match(vibr_op)
init_state = VSCF(num_modals)
num_qubits = sum(num_modals)
excitations = []
excitations += generate_vibration_excitations(num_excitations=1,
num_modals=num_modals)
excitations += generate_vibration_excitations(num_excitations=2,
num_modals=num_modals)
chc_ansatz = CHC(num_qubits,
ladder=False,
excitations=excitations,
initial_state=init_state)
backend = QuantumInstance(
BasicAer.get_backend('statevector_simulator'),
seed_transpiler=2,
seed_simulator=2)
optimizer = COBYLA(maxiter=1000)
algo = VQE(chc_ansatz, optimizer=optimizer, quantum_instance=backend)
vqe_result = algo.compute_minimum_eigenvalue(qubit_op)
energy = vqe_result.optimal_value
self.assertAlmostEqual(energy, self.reference_energy, places=4)
def test_qubits_5(self):
"""Test 2 modes 2 modals for the first mode and 3 modals for the second."""
basis = [2, 3]
vscf = VSCF(basis)
ref = QuantumCircuit(5)
ref.x([0, 2])
self.assertEqual(ref, vscf)
def test_qubits_4(self):
"""Test 2 modes 2 modals."""
basis = [2, 2]
vscf = VSCF(basis)
ref = QuantumCircuit(4)
ref.x([0, 2])
self.assertEqual(ref, vscf)
def test_chc_vscf(self):
""" chc vscf test """
co2_2modes_2modals_2body = [[[[[0, 0, 0]], 320.8467332810141],
[[[0, 1, 1]], 1760.878530705873],
[[[1, 0, 0]], 342.8218290247543],
[[[1, 1, 1]], 1032.396323618631]],
[[[[0, 0, 0], [1, 0, 0]], -57.34003649795117],
[[[0, 0, 1], [1, 0, 0]], -56.33205925807966],
[[[0, 1, 0], [1, 0, 0]], -56.33205925807966],
[[[0, 1, 1], [1, 0, 0]], -60.13032761856809],
[[[0, 0, 0], [1, 0, 1]], -65.09576309934431],
[[[0, 0, 1], [1, 0, 1]], -62.2363839133389],
[[[0, 1, 0], [1, 0, 1]], -62.2363839133389],
[[[0, 1, 1], [1, 0, 1]], -121.5533969109279],
[[[0, 0, 0], [1, 1, 0]], -65.09576309934431],
[[[0, 0, 1], [1, 1, 0]], -62.2363839133389],
[[[0, 1, 0], [1, 1, 0]], -62.2363839133389],
[[[0, 1, 1], [1, 1, 0]], -121.5533969109279],
[[[0, 0, 0], [1, 1, 1]], -170.744837386338],
[[[0, 0, 1], [1, 1, 1]], -167.7433236025723],
[[[0, 1, 0], [1, 1, 1]], -167.7433236025723],
[[[0, 1, 1], [1, 1, 1]], -179.0536532281924]]]
basis = [2, 2]
bosonic_op = BosonicOperator(co2_2modes_2modals_2body, basis)
qubit_op = bosonic_op.mapping('direct', threshold=1e-5)
with warnings.catch_warnings():
warnings.filterwarnings('ignore', category=DeprecationWarning)
init_state = VSCF(basis)
num_qubits = sum(basis)
uvcc_varform = UVCC(num_qubits, basis, [0, 1])
excitations = uvcc_varform.excitations_in_qubit_format()
chc_varform = CHC(num_qubits, ladder=False, excitations=excitations,
initial_state=init_state)
backend = QuantumInstance(BasicAer.get_backend('statevector_simulator'),
seed_transpiler=2, seed_simulator=2)
optimizer = COBYLA(maxiter=1000)
algo = VQE(chc_varform,
optimizer=optimizer,
quantum_instance=backend)
vqe_result = algo.compute_minimum_eigenvalue(qubit_op)
energy = vqe_result['optimal_value']
self.assertAlmostEqual(energy, self.reference_energy, places=4)
def get_solver( # type: ignore[override]
self,
problem: VibrationalStructureProblem,
qubit_converter: QubitConverter,
) -> MinimumEigensolver:
"""Returns a VQE with a UVCCSD wavefunction ansatz, based on ``qubit_converter``.
Args:
problem: a class encoding a problem to be solved.
qubit_converter: a class that converts second quantized operator to qubit operator
according to a mapper it is initialized with.
Returns:
A VQE suitable to compute the ground state of the molecule.
"""
basis = cast(VibrationalStructureDriverResult,
problem.grouped_property_transformed).basis
num_modals = basis.num_modals_per_mode
num_modes = len(num_modals)
if isinstance(num_modals, int):
num_modals = [num_modals] * num_modes
initial_state = self.initial_state
if initial_state is None:
initial_state = VSCF(num_modals)
ansatz = self.ansatz
if ansatz is None:
ansatz = UVCCSD()
ansatz.qubit_converter = qubit_converter
ansatz.num_modals = num_modals
ansatz.initial_state = initial_state
# TODO: leverage re-usability of VQE after fixing
# https://github.com/Qiskit/qiskit-terra/issues/7093
vqe = VQE(
ansatz=ansatz,
quantum_instance=self.quantum_instance,
optimizer=self.optimizer,
initial_point=self.initial_point,
gradient=self.gradient,
expectation=self.expectation,
include_custom=self.include_custom,
callback=self.callback,
**self._kwargs,
)
return vqe
def get_solver( # type: ignore[override]
self,
problem: VibrationalStructureProblem,
qubit_converter: QubitConverter,
) -> MinimumEigensolver:
"""Returns a VQE with a :class:`~.UVCCSD` wavefunction ansatz, based on ``qubit_converter``.
Args:
problem: a class encoding a problem to be solved.
qubit_converter: a class that converts second quantized operator to qubit operator
according to a mapper it is initialized with.
Returns:
A VQE suitable to compute the ground state of the molecule.
"""
basis = cast(VibrationalStructureDriverResult,
problem.grouped_property_transformed).basis
num_modals = basis.num_modals_per_mode
num_modes = len(num_modals)
if isinstance(num_modals, int):
num_modals = [num_modals] * num_modes
initial_state = self.initial_state
if initial_state is None:
initial_state = VSCF(num_modals)
ansatz = self._ansatz
if ansatz is None:
ansatz = UVCCSD()
ansatz.qubit_converter = qubit_converter
ansatz.num_modals = num_modals
ansatz.initial_state = initial_state
if isinstance(self.initial_point, InitialPoint):
self.initial_point.ansatz = ansatz
initial_point = self.initial_point.to_numpy_array()
else:
initial_point = self.initial_point
self.minimum_eigensolver.initial_point = initial_point
self.minimum_eigensolver.ansatz = ansatz
return self.minimum_eigensolver
def get_solver(
self,
problem: VibrationalStructureProblem, # type: ignore[override]
qubit_converter: QubitConverter
) -> MinimumEigensolver:
"""Returns a VQE with a UVCCSD wavefunction ansatz, based on ``transformation``.
This works only with a ``BosonicTransformation``.
Args:
problem: a class encoding a problem to be solved.
qubit_converter: a class that converts second quantized operator to qubit operator
according to a mapper it is initialized with.
Returns:
A VQE suitable to compute the ground state of the molecule transformed
by ``transformation``.
"""
watson_hamiltonian_transformed = cast(
WatsonHamiltonian, problem.molecule_data_transformed)
num_modals = problem.num_modals
num_modes = watson_hamiltonian_transformed.num_modes
if isinstance(num_modals, int):
num_modals = [num_modals] * num_modes
initial_state = self.initial_state
if initial_state is None:
initial_state = VSCF(num_modals)
ansatz = self.ansatz
if ansatz is None:
ansatz = UVCCSD()
ansatz.qubit_converter = qubit_converter
ansatz.num_modals = num_modals
ansatz.initial_state = initial_state
self._vqe.ansatz = ansatz
return self._vqe