def test_h2_bopes_sampler(self):
"""Test BOPES Sampler on H2"""
# Molecule
dof = partial(Molecule.absolute_distance, atom_pair=(1, 0))
m = Molecule(
geometry=[["H", [0.0, 0.0, 1.0]], ["H", [0.0, 0.45, 1.0]]],
degrees_of_freedom=[dof],
)
mapper = ParityMapper()
converter = QubitConverter(mapper=mapper, two_qubit_reduction=True)
driver = ElectronicStructureMoleculeDriver(
m, driver_type=ElectronicStructureDriverType.PYSCF)
problem = ElectronicStructureProblem(driver)
solver = NumPyMinimumEigensolver()
me_gss = GroundStateEigensolver(converter, solver)
# BOPES sampler
sampler = BOPESSampler(gss=me_gss)
# absolute internuclear distance in Angstrom
points = [0.7, 1.0, 1.3]
results = sampler.sample(problem, points)
points_run = results.points
energies = results.energies
np.testing.assert_array_almost_equal(points_run, [0.7, 1.0, 1.3])
np.testing.assert_array_almost_equal(
energies, [-1.13618945, -1.10115033, -1.03518627], decimal=2)
def test_h2_bopes_sampler_excited_eigensolver(self):
"""Test BOPES Sampler on H2"""
# Molecule
dof = partial(Molecule.absolute_distance, atom_pair=(1, 0))
m = Molecule(
geometry=[["H", [0.0, 0.0, 1.0]], ["H", [0.0, 0.45, 1.0]]],
degrees_of_freedom=[dof],
)
mapper = ParityMapper()
converter = QubitConverter(mapper=mapper)
driver = ElectronicStructureMoleculeDriver(
m, driver_type=ElectronicStructureDriverType.PYSCF)
problem = ElectronicStructureProblem(driver)
# pylint: disable=unused-argument
def filter_criterion(eigenstate, eigenvalue, aux_values):
particle_number_filter = np.isclose(
aux_values["ParticleNumber"][0], 2.0)
magnetization_filter = np.isclose(aux_values["Magnetization"][0],
0.0)
return particle_number_filter and magnetization_filter
solver = NumPyEigensolverFactory(filter_criterion=filter_criterion)
np_excited_solver = ExcitedStatesEigensolver(converter, solver)
# BOPES sampler
sampler = BOPESSampler(np_excited_solver)
# absolute internuclear distance in Angstrom
points = [0.7, 1.0, 1.3]
results = sampler.sample(problem, points)
points_run = results.points
energies = results.energies
np.testing.assert_array_almost_equal(points_run, [0.7, 1.0, 1.3])
np.testing.assert_array_almost_equal(
energies,
[
[-1.13618945, -0.47845306, -0.1204519, 0.5833141],
[-1.10115033, -0.74587179, -0.35229063, 0.03904763],
[-1.03518627, -0.85523694, -0.42240202, -0.21860355],
],
decimal=2,
)
def test_h2_bopes_sampler_qeom(self):
"""Test BOPES Sampler on H2"""
# Molecule
dof = partial(Molecule.absolute_distance, atom_pair=(1, 0))
m = Molecule(
geometry=[["H", [0.0, 0.0, 1.0]], ["H", [0.0, 0.45, 1.0]]],
degrees_of_freedom=[dof],
)
driver = ElectronicStructureMoleculeDriver(
m, driver_type=ElectronicStructureDriverType.PYSCF)
problem = ElectronicStructureProblem(driver)
qubit_converter = QubitConverter(JordanWignerMapper(),
z2symmetry_reduction=None)
quantum_instance = QuantumInstance(
backend=qiskit.providers.aer.Aer.get_backend(
"aer_simulator_statevector"),
seed_simulator=self.seed,
seed_transpiler=self.seed,
)
solver = VQE(quantum_instance=quantum_instance)
me_gsc = GroundStateEigensolver(qubit_converter, solver)
qeom_solver = QEOM(me_gsc, "sd")
# BOPES sampler
sampler = BOPESSampler(qeom_solver)
# absolute internuclear distance in Angstrom
points = [0.7, 1.0, 1.3]
results = sampler.sample(problem, points)
points_run = results.points
energies = results.energies
np.testing.assert_array_almost_equal(points_run, [0.7, 1.0, 1.3])
np.testing.assert_array_almost_equal(
energies,
[
[-1.13618945, -0.47845306, -0.1204519, 0.5833141],
[-1.10115033, -0.74587179, -0.35229063, 0.03904763],
[-1.03518627, -0.85523694, -0.42240202, -0.21860355],
],
decimal=2,
)
def test_potential_interface(self):
"""Tests potential interface."""
seed = 50
algorithm_globals.random_seed = seed
stretch = partial(Molecule.absolute_distance, atom_pair=(1, 0))
# H-H molecule near equilibrium geometry
m = Molecule(
geometry=[
["H", [0.0, 0.0, 0.0]],
["H", [1.0, 0.0, 0.0]],
],
degrees_of_freedom=[stretch],
masses=[1.6735328e-27, 1.6735328e-27],
)
mapper = ParityMapper()
converter = QubitConverter(mapper=mapper)
driver = PySCFDriver(molecule=m)
problem = ElectronicStructureProblem(driver)
solver = NumPyMinimumEigensolver()
me_gss = GroundStateEigensolver(converter, solver)
# Run BOPESSampler with exact eigensolution
points = np.arange(0.45, 5.3, 0.3)
sampler = BOPESSampler(gss=me_gss)
res = sampler.sample(problem, points)
# Testing Potential interface
pot = MorsePotential(m)
pot.fit(res.points, res.energies)
np.testing.assert_array_almost_equal([pot.alpha, pot.r_0],
[2.235, 0.720],
decimal=3)
np.testing.assert_array_almost_equal([pot.d_e, pot.m_shift],
[0.2107, -1.1419],
decimal=3)
def test_h2_bopes_sampler_with_factory(self):
"""Test BOPES Sampler with Factory"""
quantum_instance = QuantumInstance(
backend=qiskit.providers.aer.Aer.get_backend(
"aer_simulator_statevector"),
seed_simulator=self.seed,
seed_transpiler=self.seed,
)
# Molecule
distance1 = partial(Molecule.absolute_distance, atom_pair=(1, 0))
molecule = Molecule(
geometry=[("H", [0.0, 0.0, 0.0]), ("H", [0.0, 0.0, 0.6])],
degrees_of_freedom=[distance1],
)
driver = ElectronicStructureMoleculeDriver(
molecule, driver_type=ElectronicStructureDriverType.PYSCF)
problem = ElectronicStructureProblem(driver)
converter = QubitConverter(ParityMapper())
solver = GroundStateEigensolver(
converter, VQEUCCFactory(quantum_instance=quantum_instance))
sampler = BOPESSampler(solver,
bootstrap=True,
num_bootstrap=None,
extrapolator=None)
result = sampler.sample(problem, list(np.linspace(0.6, 0.8, 4)))
ref_points = [0.6, 0.6666666666666666, 0.7333333333333334, 0.8]
ref_energies = [
-1.1162853926251162,
-1.1327033478688526,
-1.137302817836066,
-1.1341458916990401,
]
np.testing.assert_almost_equal(result.points, ref_points, decimal=3)
np.testing.assert_almost_equal(result.energies,
ref_energies,
decimal=3)
def test_vqe_bootstrap(self):
"""Test with VQE and bootstrapping."""
qubit_converter = QubitConverter(JordanWignerMapper())
quantum_instance = QuantumInstance(
backend=qiskit.providers.aer.Aer.get_backend(
"aer_simulator_statevector"),
seed_simulator=self.seed,
seed_transpiler=self.seed,
)
solver = VQE(quantum_instance=quantum_instance)
vqe_gse = GroundStateEigensolver(qubit_converter, solver)
distance1 = partial(Molecule.absolute_distance, atom_pair=(1, 0))
mol = Molecule(
geometry=[("H", [0.0, 0.0, 0.0]), ("H", [0.0, 0.0, 0.6])],
degrees_of_freedom=[distance1],
)
driver = ElectronicStructureMoleculeDriver(
mol, driver_type=ElectronicStructureDriverType.PYSCF)
es_problem = ElectronicStructureProblem(driver)
points = list(np.linspace(0.6, 0.8, 4))
bopes = BOPESSampler(vqe_gse,
bootstrap=True,
num_bootstrap=None,
extrapolator=None)
result = bopes.sample(es_problem, points)
ref_points = [0.6, 0.6666666666666666, 0.7333333333333334, 0.8]
ref_energies = [
-1.1162738,
-1.1326904,
-1.1372876,
-1.1341292,
]
np.testing.assert_almost_equal(result.points, ref_points)
np.testing.assert_almost_equal(result.energies, ref_energies)
def test_h2_bopes_sampler_auxiliaries(self):
"""Test BOPES Sampler on H2"""
# Molecule
dof = partial(Molecule.absolute_distance, atom_pair=(1, 0))
m = Molecule(
geometry=[["H", [0.0, 0.0, 1.0]], ["H", [0.0, 0.45, 1.0]]],
degrees_of_freedom=[dof],
)
driver = ElectronicStructureMoleculeDriver(
m, driver_type=ElectronicStructureDriverType.PYSCF)
problem = ElectronicStructureProblem(driver)
qubit_converter = QubitConverter(JordanWignerMapper(),
z2symmetry_reduction=None)
quantum_instance = QuantumInstance(
backend=qiskit.providers.aer.Aer.get_backend(
"aer_simulator_statevector"),
seed_simulator=self.seed,
seed_transpiler=self.seed,
)
solver = VQE(quantum_instance=quantum_instance)
me_gsc = GroundStateEigensolver(qubit_converter, solver)
# Sets up the auxiliary operators
def build_hamiltonian(
current_problem: BaseProblem) -> SecondQuantizedOp:
"""Returns the SecondQuantizedOp H(R) where H is the electronic hamiltonian and R is
the current nuclear coordinates. This gives the electronic energies."""
hamiltonian_name = current_problem.main_property_name
hamiltonian_op = current_problem.second_q_ops().get(
hamiltonian_name, None)
return hamiltonian_op
aux = {
"PN":
problem.second_q_ops()["ParticleNumber"], # SecondQuantizedOp
"EN": build_hamiltonian, # Callable
"IN": PauliOp(Pauli("IIII"), 1.0), # PauliOp
}
# Note that the first item is defined once for R=0.45.
# The second item is a function of the problem giving the electronic energy.
# At each step, a perturbation is applied to the molecule degrees of freedom which updates
# the aux_operators.
# The third item is the identity written as a PauliOp, yielding the norm of the eigenstates.
# Sets up the BOPESSampler
sampler = BOPESSampler(me_gsc)
# absolute internuclear distance in Angstrom
points = [0.7, 1.0, 1.3]
results = sampler.sample(problem, points, aux_operators=aux)
points_run = results.points
particle_numbers = []
total_energies = []
norm_eigenstates = []
for results_point in list(results.raw_results.values()):
aux_op_dict = results_point.raw_result.aux_operator_eigenvalues
particle_numbers.append(aux_op_dict["PN"][0])
total_energies.append(aux_op_dict["EN"][0] +
results_point.nuclear_repulsion_energy)
norm_eigenstates.append(aux_op_dict["IN"][0])
points_run_reference = [0.7, 1.0, 1.3]
particle_numbers_reference = [2, 2, 2]
total_energies_reference = [-1.136, -1.101, -1.035]
norm_eigenstates_reference = [1, 1, 1]
np.testing.assert_array_almost_equal(points_run, points_run_reference)
np.testing.assert_array_almost_equal(particle_numbers,
particle_numbers_reference,
decimal=2)
np.testing.assert_array_almost_equal(
total_energies,
total_energies_reference,
decimal=2,
)
np.testing.assert_array_almost_equal(
norm_eigenstates,
norm_eigenstates_reference,
decimal=2,
)