def test_sparse_numerically(self):
# Check FCI energy.
energy, wavefunction = get_ground_state(self.hamiltonian_matrix)
self.assertAlmostEqual(energy, self.molecule.fci_energy)
expected_energy = expectation(self.hamiltonian_matrix, wavefunction)
self.assertAlmostEqual(expected_energy, energy)
# Make sure you can reproduce Hartree energy.
hf_state = jw_hartree_fock_state(self.molecule.n_electrons,
count_qubits(self.qubit_hamiltonian))
hf_density = get_density_matrix([hf_state], [1.])
# Make sure you can reproduce Hartree-Fock energy.
hf_state = jw_hartree_fock_state(self.molecule.n_electrons,
count_qubits(self.qubit_hamiltonian))
hf_density = get_density_matrix([hf_state], [1.])
expected_hf_density_energy = expectation(self.hamiltonian_matrix,
hf_density)
expected_hf_energy = expectation(self.hamiltonian_matrix, hf_state)
self.assertAlmostEqual(expected_hf_energy, self.molecule.hf_energy)
self.assertAlmostEqual(expected_hf_density_energy,
self.molecule.hf_energy)
def test_all(self):
# Test reverse Jordan-Wigner.
fermion_hamiltonian = reverse_jordan_wigner(self.qubit_hamiltonian)
fermion_hamiltonian = normal_ordered(fermion_hamiltonian)
self.assertTrue(self.fermion_hamiltonian == fermion_hamiltonian)
# Test mapping to interaction operator.
fermion_hamiltonian = get_fermion_operator(self.molecular_hamiltonian)
fermion_hamiltonian = normal_ordered(fermion_hamiltonian)
self.assertTrue(self.fermion_hamiltonian == fermion_hamiltonian)
# Test RDM energy.
fci_rdm_energy = self.nuclear_repulsion
fci_rdm_energy += numpy.sum(self.fci_rdm.one_body_tensor *
self.one_body)
fci_rdm_energy += numpy.sum(self.fci_rdm.two_body_tensor *
self.two_body)
self.assertAlmostEqual(fci_rdm_energy, self.molecule.fci_energy)
# Confirm expectation on qubit Hamiltonian using reverse JW matches.
qubit_rdm = self.fci_rdm.get_qubit_expectations(self.qubit_hamiltonian)
qubit_energy = 0.0
for term, coefficient in qubit_rdm.terms.items():
qubit_energy += coefficient * self.qubit_hamiltonian.terms[term]
self.assertAlmostEqual(qubit_energy, self.molecule.fci_energy)
# Confirm fermionic RDMs can be built from measured qubit RDMs.
new_fermi_rdm = get_interaction_rdm(qubit_rdm)
new_fermi_rdm.expectation(self.molecular_hamiltonian)
self.assertAlmostEqual(fci_rdm_energy, self.molecule.fci_energy)
# Test sparse matrices.
energy, wavefunction = get_ground_state(self.hamiltonian_matrix)
self.assertAlmostEqual(energy, self.molecule.fci_energy)
expected_energy = expectation(self.hamiltonian_matrix, wavefunction)
self.assertAlmostEqual(expected_energy, energy)
# Make sure you can reproduce Hartree-Fock energy.
hf_state = jw_hartree_fock_state(self.molecule.n_electrons,
count_qubits(self.qubit_hamiltonian))
hf_density = get_density_matrix([hf_state], [1.])
expected_hf_density_energy = expectation(self.hamiltonian_matrix,
hf_density)
expected_hf_energy = expectation(self.hamiltonian_matrix, hf_state)
self.assertAlmostEqual(expected_hf_energy, self.molecule.hf_energy)
self.assertAlmostEqual(expected_hf_density_energy,
self.molecule.hf_energy)
# Check that frozen core result matches frozen core FCI from psi4.
# Recore frozen core result from external calculation.
self.frozen_core_fci_energy = -7.8807607374168
no_core_fci_energy = numpy.linalg.eigh(
self.hamiltonian_matrix_no_core.toarray())[0][0]
self.assertAlmostEqual(no_core_fci_energy, self.frozen_core_fci_energy)
# Check that the freeze_orbitals function has the same effect as the
# as the occupied_indices option of get_molecular_hamiltonian.
frozen_hamiltonian = freeze_orbitals(
get_fermion_operator(self.molecular_hamiltonian), [0, 1])
self.assertTrue(frozen_hamiltonian == get_fermion_operator(
self.molecular_hamiltonian_no_core))
def test_ucc_h2_singlet(self):
geometry = [('H', (0., 0., 0.)), ('H', (0., 0., 0.7414))]
basis = 'sto-3g'
multiplicity = 1
filename = os.path.join(THIS_DIRECTORY, 'data',
'H2_sto-3g_singlet_0.7414')
self.molecule = MolecularData(geometry,
basis,
multiplicity,
filename=filename)
self.molecule.load()
# Get molecular Hamiltonian.
self.molecular_hamiltonian = self.molecule.get_molecular_hamiltonian()
# Get FCI RDM.
self.fci_rdm = self.molecule.get_molecular_rdm(use_fci=1)
# Get explicit coefficients.
self.nuclear_repulsion = self.molecular_hamiltonian.constant
self.one_body = self.molecular_hamiltonian.one_body_tensor
self.two_body = self.molecular_hamiltonian.two_body_tensor
# Get fermion Hamiltonian.
self.fermion_hamiltonian = normal_ordered(
get_fermion_operator(self.molecular_hamiltonian))
# Get qubit Hamiltonian.
self.qubit_hamiltonian = jordan_wigner(self.fermion_hamiltonian)
# Get the sparse matrix.
self.hamiltonian_matrix = get_sparse_operator(
self.molecular_hamiltonian)
# Test UCCSD for accuracy against FCI using loaded t amplitudes.
ucc_operator = uccsd_generator(self.molecule.ccsd_single_amps,
self.molecule.ccsd_double_amps)
hf_state = jw_hartree_fock_state(self.molecule.n_electrons,
count_qubits(self.qubit_hamiltonian))
uccsd_sparse = jordan_wigner_sparse(ucc_operator)
uccsd_state = scipy.sparse.linalg.expm_multiply(uccsd_sparse, hf_state)
expected_uccsd_energy = expectation(self.hamiltonian_matrix,
uccsd_state)
self.assertAlmostEqual(expected_uccsd_energy,
self.molecule.fci_energy,
places=4)
print("UCCSD ENERGY: {}".format(expected_uccsd_energy))
# Test CCSD singlet for precise match against FCI using loaded t
# amplitudes
packed_amplitudes = uccsd_singlet_get_packed_amplitudes(
self.molecule.ccsd_single_amps, self.molecule.ccsd_double_amps,
self.molecule.n_qubits, self.molecule.n_electrons)
ccsd_operator = uccsd_singlet_generator(packed_amplitudes,
self.molecule.n_qubits,
self.molecule.n_electrons,
anti_hermitian=False)
ccsd_sparse_r = jordan_wigner_sparse(ccsd_operator)
ccsd_sparse_l = jordan_wigner_sparse(
-hermitian_conjugated(ccsd_operator))
ccsd_state_r = scipy.sparse.linalg.expm_multiply(
ccsd_sparse_r, hf_state)
ccsd_state_l = scipy.sparse.linalg.expm_multiply(
ccsd_sparse_l, hf_state)
expected_ccsd_energy = ccsd_state_l.conjugate().dot(
self.hamiltonian_matrix.dot(ccsd_state_r))
self.assertAlmostEqual(expected_ccsd_energy, self.molecule.fci_energy)