def test_qpe(self, distance):
self.algorithm = 'QPE'
self.log.debug('Testing End-to-End with QPE on H2 with inter-atomic distance {}.'.format(distance))
try:
driver = PySCFDriver(atom='H .0 .0 .0; H .0 .0 {}'.format(distance),
unit=UnitsType.ANGSTROM,
charge=0,
spin=0,
basis='sto3g')
except QiskitChemistryError:
self.skipTest('PYSCF driver does not appear to be installed')
self.molecule = driver.run()
qubit_mapping = 'parity'
fer_op = FermionicOperator(
h1=self.molecule.one_body_integrals, h2=self.molecule.two_body_integrals)
self.qubit_op = fer_op.mapping(map_type=qubit_mapping,
threshold=1e-10).two_qubit_reduced_operator(2)
exact_eigensolver = ExactEigensolver(self.qubit_op, k=1)
results = exact_eigensolver.run()
self.reference_energy = results['energy']
self.log.debug(
'The exact ground state energy is: {}'.format(results['energy']))
num_particles = self.molecule.num_alpha + self.molecule.num_beta
two_qubit_reduction = True
num_orbitals = self.qubit_op.num_qubits + \
(2 if two_qubit_reduction else 0)
num_time_slices = 50
n_ancillae = 9
state_in = HartreeFock(self.qubit_op.num_qubits, num_orbitals,
num_particles, qubit_mapping, two_qubit_reduction)
iqft = Standard(n_ancillae)
qpe = QPE(self.qubit_op, state_in, iqft, num_time_slices, n_ancillae,
expansion_mode='suzuki',
expansion_order=2, shallow_circuit_concat=True)
backend = qiskit.Aer.get_backend('qasm_simulator')
run_config = RunConfig(shots=100, max_credits=10, memory=False)
quantum_instance = QuantumInstance(backend, run_config, pass_manager=PassManager())
result = qpe.run(quantum_instance)
self.log.debug('eigvals: {}'.format(result['eigvals']))
self.log.debug('top result str label: {}'.format(result['top_measurement_label']))
self.log.debug('top result in decimal: {}'.format(result['top_measurement_decimal']))
self.log.debug('stretch: {}'.format(result['stretch']))
self.log.debug('translation: {}'.format(result['translation']))
self.log.debug('final energy from QPE: {}'.format(result['energy']))
self.log.debug('reference energy: {}'.format(self.reference_energy))
self.log.debug('ref energy (transformed): {}'.format(
(self.reference_energy + result['translation']) * result['stretch']))
self.log.debug('ref binary str label: {}'.format(decimal_to_binary((self.reference_energy + result['translation']) * result['stretch'],
max_num_digits=n_ancillae + 3,
fractional_part_only=True)))
np.testing.assert_approx_equal(
result['energy'], self.reference_energy, significant=2)
def test_qpe(self, distance):
""" qpe test """
self.log.debug('Testing End-to-End with QPE on '
'H2 with inter-atomic distance %s.', distance)
try:
driver = PySCFDriver(atom='H .0 .0 .0; H .0 .0 {}'.format(distance),
unit=UnitsType.ANGSTROM,
charge=0,
spin=0,
basis='sto3g')
except QiskitChemistryError:
self.skipTest('PYSCF driver does not appear to be installed')
molecule = driver.run()
qubit_mapping = 'parity'
fer_op = FermionicOperator(
h1=molecule.one_body_integrals, h2=molecule.two_body_integrals)
qubit_op = fer_op.mapping(map_type=qubit_mapping, threshold=1e-10)
qubit_op = Z2Symmetries.two_qubit_reduction(qubit_op, 2)
exact_eigensolver = ExactEigensolver(qubit_op, k=1)
results = exact_eigensolver.run()
reference_energy = results['energy']
self.log.debug('The exact ground state energy is: %s', results['energy'])
num_particles = molecule.num_alpha + molecule.num_beta
two_qubit_reduction = True
num_orbitals = qubit_op.num_qubits + \
(2 if two_qubit_reduction else 0)
num_time_slices = 1
n_ancillae = 6
state_in = HartreeFock(qubit_op.num_qubits, num_orbitals,
num_particles, qubit_mapping, two_qubit_reduction)
iqft = Standard(n_ancillae)
qpe = QPE(qubit_op, state_in, iqft, num_time_slices, n_ancillae,
expansion_mode='suzuki',
expansion_order=2, shallow_circuit_concat=True)
backend = qiskit.BasicAer.get_backend('qasm_simulator')
quantum_instance = QuantumInstance(backend, shots=100)
result = qpe.run(quantum_instance)
self.log.debug('eigvals: %s', result['eigvals'])
self.log.debug('top result str label: %s', result['top_measurement_label'])
self.log.debug('top result in decimal: %s', result['top_measurement_decimal'])
self.log.debug('stretch: %s', result['stretch'])
self.log.debug('translation: %s', result['translation'])
self.log.debug('final energy from QPE: %s', result['energy'])
self.log.debug('reference energy: %s', reference_energy)
self.log.debug('ref energy (transformed): %s',
(reference_energy + result['translation']) * result['stretch'])
self.log.debug('ref binary str label: %s',
decimal_to_binary(
(reference_energy + result['translation']) * result['stretch'],
max_num_digits=n_ancillae + 3, fractional_part_only=True))
np.testing.assert_approx_equal(result['energy'], reference_energy, significant=2)