Beispiel #1
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    def test_mapping_for_single_op(self):
        """Test for single register operator."""
        with self.subTest("test +"):
            op = FermionicOp("+", display_format="dense")
            expected = PauliSumOp.from_list([("X", 0.5), ("Y", -0.5j)])
            self.assertEqual(ParityMapper().map(op), expected)

        with self.subTest("test -"):
            op = FermionicOp("-", display_format="dense")
            expected = PauliSumOp.from_list([("X", 0.5), ("Y", 0.5j)])
            self.assertEqual(ParityMapper().map(op), expected)

        with self.subTest("test N"):
            op = FermionicOp("N", display_format="dense")
            expected = PauliSumOp.from_list([("I", 0.5), ("Z", -0.5)])
            self.assertEqual(ParityMapper().map(op), expected)

        with self.subTest("test E"):
            op = FermionicOp("E", display_format="dense")
            expected = PauliSumOp.from_list([("I", 0.5), ("Z", 0.5)])
            self.assertEqual(ParityMapper().map(op), expected)

        with self.subTest("test I"):
            op = FermionicOp("I", display_format="dense")
            expected = PauliSumOp.from_list([("I", 1)])
            self.assertEqual(ParityMapper().map(op), expected)
Beispiel #2
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    def test_mapping(self):
        """Test mapping to qubit operator"""
        driver = HDF5Driver(hdf5_input=self.get_resource_path(
            "test_driver_hdf5.hdf5", "second_q/drivers/hdf5d"))
        driver_result = driver.run()
        fermionic_op = driver_result.second_q_ops()["ElectronicEnergy"]
        mapper = ParityMapper()
        qubit_op = mapper.map(fermionic_op)

        # Note: The PauliSumOp equals, as used in the test below, use the equals of the
        #       SparsePauliOp which in turn uses np.allclose() to determine equality of
        #       coeffs. So the reference operator above will be matched on that basis so
        #       we don't need to worry about tiny precision changes for any reason.

        self.assertEqual(qubit_op, TestParityMapper.REF_H2)
    def test_two_qubit_reduction_and_z2_symmetry(self):
        """Test mapping to qubit operator with z2 symmetry tapering and two qubit reduction"""
        z2_sector = [-1]

        def cb_finder(z2_symmetries: Z2Symmetries,
                      converter: QubitConverter) -> Optional[List[int]]:
            return z2_sector if not z2_symmetries.is_empty() else None

        mapper = ParityMapper()
        qubit_conv = QubitConverter(mapper,
                                    two_qubit_reduction=True,
                                    z2symmetry_reduction="auto")
        qubit_op = qubit_conv.convert(self.h2_op,
                                      self.num_particles,
                                      sector_locator=cb_finder)
        self.assertEqual(qubit_op,
                         TestQubitConverter.REF_H2_PARITY_2Q_REDUCED_TAPER)
        self.assertEqual(qubit_conv.num_particles, self.num_particles)
        self.assertListEqual(qubit_conv.z2symmetries.tapering_values,
                             z2_sector)

        with self.subTest("convert_match()"):
            qubit_op = qubit_conv.convert_match(self.h2_op)
            self.assertEqual(qubit_op,
                             TestQubitConverter.REF_H2_PARITY_2Q_REDUCED_TAPER)
            self.assertEqual(qubit_conv.num_particles, self.num_particles)
            self.assertListEqual(qubit_conv.z2symmetries.tapering_values,
                                 z2_sector)

        with self.subTest("Change setting"):
            qubit_conv.z2symmetry_reduction = [1]
            qubit_op = qubit_conv.convert(self.h2_op, self.num_particles)
            self.assertNotEqual(
                qubit_op, TestQubitConverter.REF_H2_PARITY_2Q_REDUCED_TAPER)
            qubit_conv.z2symmetry_reduction = [-1]
            qubit_op = qubit_conv.convert(self.h2_op, self.num_particles)
            self.assertEqual(qubit_op,
                             TestQubitConverter.REF_H2_PARITY_2Q_REDUCED_TAPER)

        with self.subTest("Specify sector upfront"):
            qubit_conv = QubitConverter(mapper,
                                        two_qubit_reduction=True,
                                        z2symmetry_reduction=z2_sector)
            qubit_op = qubit_conv.convert(self.h2_op, self.num_particles)
            self.assertEqual(qubit_op,
                             TestQubitConverter.REF_H2_PARITY_2Q_REDUCED_TAPER)

        with self.subTest("Specify sector upfront, but invalid content"):
            with self.assertRaises(ValueError):
                _ = QubitConverter(mapper,
                                   two_qubit_reduction=True,
                                   z2symmetry_reduction=[5])

        with self.subTest("Specify sector upfront, but invalid length"):
            qubit_conv = QubitConverter(mapper,
                                        two_qubit_reduction=True,
                                        z2symmetry_reduction=[-1, 1])
            with self.assertRaises(QiskitNatureError):
                _ = qubit_conv.convert(self.h2_op, self.num_particles)
Beispiel #4
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 def test_qubits_2_py_h2(self):
     """qubits 2 py h2 test"""
     num_particles = (1, 1)
     converter = QubitConverter(ParityMapper(), two_qubit_reduction=True)
     converter.force_match(num_particles=num_particles)
     state = HartreeFock(4, num_particles, converter)
     ref = QuantumCircuit(2)
     ref.x(0)
     self.assertEqual(state, ref)
Beispiel #5
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 def test_hf_bitstring_mapped(self):
     """Mapped bitstring test for water"""
     # Original driver config when creating operator that resulted in symmetries coded
     # below. The sector [1, -1] is the correct ground sector.
     # PySCFDriver(
     #    atom="O 0.0000 0.0000 0.1173; H 0.0000 0.07572 -0.4692;H 0.0000 -0.07572 -0.4692",
     #    unit=UnitsType.ANGSTROM,
     #    charge=0,
     #    spin=0,
     #    basis='sto-3g',
     #    hf_method=HFMethodType.RHF)
     num_spin_orbitals = 14
     num_particles = (5, 5)
     converter = QubitConverter(ParityMapper(), two_qubit_reduction=True)
     z2symmetries = Z2Symmetries(
         symmetries=[Pauli("IZZIIIIZZIII"),
                     Pauli("ZZIZIIZZIZII")],
         sq_paulis=[Pauli("IIIIIIIIXIII"),
                    Pauli("IIIIIIIIIXII")],
         sq_list=[3, 2],
         tapering_values=[1, -1],
     )
     with self.subTest("Matched bitsring creation"):
         converter.force_match(num_particles=num_particles,
                               z2symmetries=z2symmetries)
         bitstr = hartree_fock_bitstring_mapped(
             num_spin_orbitals=num_spin_orbitals,
             num_particles=num_particles,
             qubit_converter=converter,
         )
         ref_matched = [
             True, False, True, True, False, True, False, True, False, False
         ]
         self.assertListEqual(bitstr, ref_matched)
     with self.subTest("Bitsring creation with no tapering"):
         bitstr = hartree_fock_bitstring_mapped(
             num_spin_orbitals=num_spin_orbitals,
             num_particles=num_particles,
             qubit_converter=converter,
             match_convert=False,
         )
         ref_notaper = [
             True,
             False,
             True,
             False,
             True,
             True,
             False,
             True,
             False,
             True,
             False,
             False,
         ]
         self.assertListEqual(bitstr, ref_notaper)
    def test_two_qubit_reduction(self):
        """Test mapping to qubit operator with two qubit reduction"""
        mapper = ParityMapper()
        qubit_conv = QubitConverter(mapper, two_qubit_reduction=True)

        with self.subTest(
                "Two qubit reduction ignored as no num particles given"):
            qubit_op = qubit_conv.convert(self.h2_op)
            self.assertEqual(qubit_op, TestQubitConverter.REF_H2_PARITY)
            self.assertIsNone(qubit_conv.num_particles)

        with self.subTest("Two qubit reduction, num particles given"):
            qubit_op = qubit_conv.convert(self.h2_op, self.num_particles)
            self.assertEqual(qubit_op,
                             TestQubitConverter.REF_H2_PARITY_2Q_REDUCED)
            self.assertEqual(qubit_conv.num_particles, self.num_particles)

        with self.subTest("convert_match()"):
            qubit_op = qubit_conv.convert_match(self.h2_op)
            self.assertEqual(qubit_op,
                             TestQubitConverter.REF_H2_PARITY_2Q_REDUCED)
            self.assertEqual(qubit_conv.num_particles, self.num_particles)

        with self.subTest("State is reset (Num particles lost)"):
            qubit_op = qubit_conv.convert(self.h2_op)
            self.assertEqual(qubit_op, TestQubitConverter.REF_H2_PARITY)
            self.assertIsNone(qubit_conv.num_particles)

        with self.subTest("Num particles given again"):
            qubit_op = qubit_conv.convert(self.h2_op, self.num_particles)
            self.assertEqual(qubit_op,
                             TestQubitConverter.REF_H2_PARITY_2Q_REDUCED)

        with self.subTest("Set for no two qubit reduction"):
            qubit_conv.two_qubit_reduction = False
            self.assertFalse(qubit_conv.two_qubit_reduction)
            qubit_op = qubit_conv.convert(self.h2_op)
            self.assertEqual(qubit_op, TestQubitConverter.REF_H2_PARITY)

        # Regression test against https://github.com/Qiskit/qiskit-nature/issues/271
        with self.subTest(
                "Two qubit reduction skipped when operator too small"):
            qubit_conv.two_qubit_reduction = True
            small_op = FermionicOp([("N_0", 1.0), ("E_1", 1.0)],
                                   register_length=2,
                                   display_format="sparse")
            expected_op = 1.0 * (I ^ I) - 0.5 * (I ^ Z) + 0.5 * (Z ^ Z)
            with contextlib.redirect_stderr(io.StringIO()) as out:
                qubit_op = qubit_conv.convert(small_op,
                                              num_particles=self.num_particles)
            self.assertEqual(qubit_op, expected_op)
            self.assertTrue(out.getvalue().strip().startswith(
                "The original qubit operator only contains 2 qubits! "
                "Skipping the requested two-qubit reduction!"))
Beispiel #7
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 def test_oh_uhf_parity(self):
     """oh uhf parity test"""
     driver = PySCFDriver(
         atom=self.o_h,
         unit=UnitsType.ANGSTROM,
         charge=0,
         spin=1,
         basis="sto-3g",
         method=MethodType.UHF,
     )
     result = self._run_driver(driver,
                               converter=QubitConverter(ParityMapper()))
     self._assert_energy_and_dipole(result, "oh")
Beispiel #8
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 def test_oh_rohf_parity_2q(self):
     """oh rohf parity 2q test"""
     driver = PySCFDriver(
         atom=self.o_h,
         unit=UnitsType.ANGSTROM,
         charge=0,
         spin=1,
         basis="sto-3g",
         method=MethodType.ROHF,
     )
     result = self._run_driver(
         driver,
         converter=QubitConverter(ParityMapper(), two_qubit_reduction=True))
     self._assert_energy_and_dipole(result, "oh")
Beispiel #9
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 def test_lih_rhf_parity_2q(self):
     """lih rhf parity 2q test"""
     driver = PySCFDriver(
         atom=self.lih,
         unit=UnitsType.ANGSTROM,
         charge=0,
         spin=0,
         basis="sto-3g",
         method=MethodType.RHF,
     )
     result = self._run_driver(
         driver,
         converter=QubitConverter(ParityMapper(), two_qubit_reduction=True),
         transformers=[FreezeCoreTransformer()],
     )
     self._assert_energy_and_dipole(result, "lih")
Beispiel #10
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 def test_sector_locator_h2o(self):
     """Test sector locator."""
     driver = PySCFDriver(
         atom="O 0.0000 0.0000 0.1173; H 0.0000 0.07572 -0.4692;H 0.0000 -0.07572 -0.4692",
         basis="sto-3g",
     )
     es_problem = ElectronicStructureProblem(driver)
     qubit_conv = QubitConverter(
         mapper=ParityMapper(), two_qubit_reduction=True, z2symmetry_reduction="auto"
     )
     main_op, _ = es_problem.second_q_ops()
     qubit_conv.convert(
         main_op,
         num_particles=es_problem.num_particles,
         sector_locator=es_problem.symmetry_sector_locator,
     )
     self.assertListEqual(qubit_conv.z2symmetries.tapering_values, [1, -1])
Beispiel #11
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 def test_qubits_6_py_lih(self):
     """qubits 6 py lih test"""
     num_particles = (1, 1)
     converter = QubitConverter(ParityMapper(), two_qubit_reduction=True)
     z2symmetries = Z2Symmetries(
         symmetries=[Pauli("ZIZIZIZI"),
                     Pauli("ZZIIZZII")],
         sq_paulis=[Pauli("IIIIIIXI"), Pauli("IIIIIXII")],
         sq_list=[2, 3],
         tapering_values=[1, 1],
     )
     converter.force_match(num_particles=num_particles,
                           z2symmetries=z2symmetries)
     state = HartreeFock(10, num_particles, converter)
     ref = QuantumCircuit(6)
     ref.x([0, 1])
     self.assertEqual(state, ref)
    def setUp(self):
        super().setUp()
        self.driver = PySCFDriver(atom="H 0 0 0.735; H 0 0 0", basis="631g")

        self.qubit_converter = QubitConverter(ParityMapper(), two_qubit_reduction=True)

        self.electronic_structure_problem = ElectronicStructureProblem(
            self.driver, [FreezeCoreTransformer()]
        )

        self.num_spin_orbitals = 8
        self.num_particles = (1, 1)

        # because we create the initial state and ansatzes early, we need to ensure the qubit
        # converter already ran such that convert_match works as expected
        main_op, _ = self.electronic_structure_problem.second_q_ops()
        _ = self.qubit_converter.convert(
            main_op,
            self.num_particles,
        )

        self.reference_energy_pUCCD = -1.1434447924298028
        self.reference_energy_UCCD0 = -1.1476045878481704
        self.reference_energy_UCCD0full = -1.1515491334334347
        # reference energy of UCCSD/VQE with tapering everywhere
        self.reference_energy_UCCSD = -1.1516142309717594
        # reference energy of UCCSD/VQE when no tapering on excitations is used
        self.reference_energy_UCCSD_no_tap_exc = -1.1516142309717594
        # excitations for succ
        self.reference_singlet_double_excitations = [
            [0, 1, 4, 5],
            [0, 1, 4, 6],
            [0, 1, 4, 7],
            [0, 2, 4, 6],
            [0, 2, 4, 7],
            [0, 3, 4, 7],
        ]
        # groups for succ_full
        self.reference_singlet_groups = [
            [[0, 1, 4, 5]],
            [[0, 1, 4, 6], [0, 2, 4, 5]],
            [[0, 1, 4, 7], [0, 3, 4, 5]],
            [[0, 2, 4, 6]],
            [[0, 2, 4, 7], [0, 3, 4, 6]],
            [[0, 3, 4, 7]],
        ]
Beispiel #13
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    def setUp(self):
        super().setUp()
        algorithm_globals.random_seed = 42

        driver = HDF5Driver(hdf5_input=self.get_resource_path(
            "test_driver_hdf5.hdf5", "second_q/drivers/hdf5d"))
        problem = ElectronicStructureProblem(driver)
        main_op, aux_ops = problem.second_q_ops()
        converter = QubitConverter(mapper=ParityMapper(),
                                   two_qubit_reduction=True)
        num_particles = (
            problem.grouped_property_transformed.get_property(
                "ParticleNumber").num_alpha,
            problem.grouped_property_transformed.get_property(
                "ParticleNumber").num_beta,
        )
        self.qubit_op = converter.convert(main_op, num_particles)
        self.aux_ops = converter.convert_match(aux_ops)
        self.reference_energy = -1.857275027031588
Beispiel #14
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    def test_excitation_preserving(self):
        """Test the excitation preserving wavefunction on a chemistry example."""

        driver = HDF5Driver(
            self.get_resource_path("test_driver_hdf5.hdf5",
                                   "second_q/drivers/hdf5d"))

        converter = QubitConverter(ParityMapper())

        problem = ElectronicStructureProblem(driver)

        _ = problem.second_q_ops()

        particle_number = cast(
            ParticleNumber,
            problem.grouped_property_transformed.get_property(ParticleNumber))
        num_particles = (particle_number.num_alpha, particle_number.num_beta)
        num_spin_orbitals = particle_number.num_spin_orbitals

        optimizer = SLSQP(maxiter=100)

        initial_state = HartreeFock(num_spin_orbitals, num_particles,
                                    converter)

        wavefunction = ExcitationPreserving(num_spin_orbitals)
        wavefunction.compose(initial_state, front=True, inplace=True)

        solver = VQE(
            ansatz=wavefunction,
            optimizer=optimizer,
            quantum_instance=QuantumInstance(
                BasicAer.get_backend("statevector_simulator"),
                seed_simulator=algorithm_globals.random_seed,
                seed_transpiler=algorithm_globals.random_seed,
            ),
        )

        gsc = GroundStateEigensolver(converter, solver)

        result = gsc.solve(problem)
        self.assertAlmostEqual(result.total_energies[0],
                               self.reference_energy,
                               places=4)
Beispiel #15
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 def test_sector_locator_homonuclear(self):
     """Test sector locator."""
     molecule = Molecule(
         geometry=[("Li", [0.0, 0.0, 0.0]), ("Li", [0.0, 0.0, 2.771])], charge=0, multiplicity=1
     )
     freeze_core_transformer = FreezeCoreTransformer(True)
     driver = ElectronicStructureMoleculeDriver(
         molecule, basis="sto3g", driver_type=ElectronicStructureDriverType.PYSCF
     )
     es_problem = ElectronicStructureProblem(driver, transformers=[freeze_core_transformer])
     qubit_conv = QubitConverter(
         mapper=ParityMapper(), two_qubit_reduction=True, z2symmetry_reduction="auto"
     )
     main_op, _ = es_problem.second_q_ops()
     qubit_conv.convert(
         main_op,
         num_particles=es_problem.num_particles,
         sector_locator=es_problem.symmetry_sector_locator,
     )
     self.assertListEqual(qubit_conv.z2symmetries.tapering_values, [-1, 1])
    def test_freeze_core_z2_symmetry_compatibility(self):
        """Regression test against #192.

        An issue arose when the FreezeCoreTransformer was combined with the automatic Z2Symmetry
        reduction. This regression test ensures that this behavior remains fixed.
        """
        driver = HDF5Driver(hdf5_input=self.get_resource_path(
            "LiH_sto3g.hdf5", "second_q/transformers"))
        problem = ElectronicStructureProblem(driver, [FreezeCoreTransformer()])
        qubit_converter = QubitConverter(
            ParityMapper(),
            two_qubit_reduction=True,
            z2symmetry_reduction="auto",
        )

        solver = NumPyMinimumEigensolverFactory()
        gsc = GroundStateEigensolver(qubit_converter, solver)

        result = gsc.solve(problem)
        self.assertAlmostEqual(result.total_energies[0], -7.882, places=2)
    def test_mapping_basic(self):
        """Test mapping to qubit operator"""
        mapper = JordanWignerMapper()
        qubit_conv = QubitConverter(mapper)
        qubit_op = qubit_conv.convert(self.h2_op)

        self.assertIsInstance(qubit_op, PauliSumOp)

        # Note: The PauliSumOp equals, as used in the test below, use the equals of the
        #       SparsePauliOp which in turn uses np.allclose() to determine equality of
        #       coeffs. So the reference operator above will be matched on that basis so
        #       we don't need to worry about tiny precision changes for any reason.

        self.assertEqual(qubit_op, TestQubitConverter.REF_H2_JW)

        with self.subTest("Re-use test"):
            qubit_op = qubit_conv.convert(self.h2_op)
            self.assertEqual(qubit_op, TestQubitConverter.REF_H2_JW)

        with self.subTest("convert_match()"):
            qubit_op = qubit_conv.convert_match(self.h2_op)
            self.assertEqual(qubit_op, TestQubitConverter.REF_H2_JW)

        with self.subTest("Re-use with different mapper"):
            qubit_conv.mapper = ParityMapper()
            qubit_op = qubit_conv.convert(self.h2_op)
            self.assertEqual(qubit_op, TestQubitConverter.REF_H2_PARITY)

        with self.subTest(
                "Set two qubit reduction - no effect without num particles"):
            qubit_conv.two_qubit_reduction = True
            qubit_op = qubit_conv.convert_match(self.h2_op)
            self.assertEqual(qubit_op, TestQubitConverter.REF_H2_PARITY)

        with self.subTest("Force match set num particles"):
            qubit_conv.force_match(self.num_particles)
            qubit_op = qubit_conv.convert_match(self.h2_op)
            self.assertEqual(qubit_op,
                             TestQubitConverter.REF_H2_PARITY_2Q_REDUCED)
    def test_uccsd_hf_qasm(self):
        """uccsd hf test with qasm simulator."""
        qubit_converter = QubitConverter(ParityMapper())
        ansatz = self._prepare_uccsd_hf(qubit_converter)

        backend = BasicAer.get_backend("qasm_simulator")

        optimizer = SPSA(maxiter=200, last_avg=5)
        solver = VQE(
            ansatz=ansatz,
            optimizer=optimizer,
            expectation=PauliExpectation(),
            quantum_instance=QuantumInstance(
                backend=backend,
                seed_simulator=algorithm_globals.random_seed,
                seed_transpiler=algorithm_globals.random_seed,
            ),
        )

        gsc = GroundStateEigensolver(qubit_converter, solver)

        result = gsc.solve(self.electronic_structure_problem)
        self.assertAlmostEqual(result.total_energies[0], -1.138, places=2)
Beispiel #19
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 def test_qubits_4_py_h2(self):
     """qubits 4 py h2 test"""
     state = HartreeFock(4, (1, 1), QubitConverter(ParityMapper()))
     ref = QuantumCircuit(4)
     ref.x([0, 1])
     self.assertEqual(state, ref)
 def test_vqe_mes_parity(self):
     """Test VQEUCCSDFactory with QEOM + Parity mapping"""
     converter = QubitConverter(ParityMapper())
     self._solve_with_vqe_mes(converter)
 def test_vqe_mes_parity_2q_auto(self):
     """Test VQEUCCSDFactory with QEOM + Parity mapping + reduction + auto symmetry"""
     converter = QubitConverter(ParityMapper(),
                                two_qubit_reduction=True,
                                z2symmetry_reduction="auto")
     self._solve_with_vqe_mes(converter)
 def test_vqe_mes_parity_2q(self):
     """Test VQEUCCSDFactory with QEOM + Parity mapping + reduction"""
     converter = QubitConverter(ParityMapper(), two_qubit_reduction=True)
     self._solve_with_vqe_mes(converter)
Beispiel #23
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 def test_allows_two_qubit_reduction(self):
     """Test this returns True for this mapper"""
     mapper = ParityMapper()
     self.assertTrue(mapper.allows_two_qubit_reduction)
Beispiel #24
0
    def test_build_ucc(self):
        """Test building UCC"""
        ucc = UCC()

        with self.subTest("Check defaulted construction"):
            self.assertIsNone(ucc.num_particles)
            self.assertIsNone(ucc.num_spin_orbitals)
            self.assertIsNone(ucc.excitations)
            self.assertIsNone(ucc.qubit_converter)
            self.assertIsNone(ucc.operators)
            self.assertIsNone(ucc.excitation_list)
            self.assertEqual(ucc.num_qubits, 0)
            with self.assertRaises(ValueError):
                _ = ucc.data

        with self.subTest("Set num particles"):
            ucc.num_particles = (1, 1)
            self.assertEqual(ucc.num_particles, (1, 1))
            self.assertIsNone(ucc.operators)
            with self.assertRaises(ValueError):
                _ = ucc.data

        with self.subTest("Set num spin orbitals"):
            ucc.num_spin_orbitals = 4
            self.assertEqual(ucc.num_spin_orbitals, 4)
            self.assertIsNone(ucc.operators)
            with self.assertRaises(ValueError):
                _ = ucc.data

        with self.subTest("Set excitations"):
            ucc.excitations = "sd"
            self.assertEqual(ucc.excitations, "sd")
            self.assertIsNone(ucc.operators)
            with self.assertRaises(ValueError):
                _ = ucc.data

        with self.subTest("Set qubit converter to complete build"):
            converter = QubitConverter(JordanWignerMapper())
            ucc.qubit_converter = converter
            self.assertEqual(ucc.qubit_converter, converter)
            self.assertIsNotNone(ucc.operators)
            self.assertEqual(len(ucc.operators), 3)
            self.assertEqual(ucc.num_qubits, 4)
            self.assertIsNotNone(ucc.data)

        with self.subTest("Set custom operators"):
            self.assertEqual(len(ucc.operators), 3)
            ucc.operators = ucc.operators[:2]
            self.assertEqual(len(ucc.operators), 2)
            self.assertEqual(ucc.num_qubits, 4)

        with self.subTest("Reset operators back to as per UCC"):
            ucc.operators = None
            self.assertEqual(ucc.num_qubits, 4)
            self.assertIsNotNone(ucc.operators)
            self.assertEqual(len(ucc.operators), 3)

        with self.subTest("Set num particles to include 0"):
            ucc.num_particles = (1, 0)
            self.assertEqual(ucc.num_particles, (1, 0))
            self.assertIsNotNone(ucc.operators)
            self.assertEqual(len(ucc.operators), 1)

        with self.subTest("Change num particles"):
            ucc.num_particles = (1, 1)
            self.assertIsNotNone(ucc.operators)
            self.assertEqual(len(ucc.operators), 3)

        with self.subTest("Change num spin orbitals"):
            ucc.num_spin_orbitals = 6
            self.assertIsNotNone(ucc.operators)
            self.assertEqual(len(ucc.operators), 8)

        with self.subTest("Change excitations"):
            ucc.excitations = "s"
            self.assertIsNotNone(ucc.operators)
            self.assertEqual(len(ucc.operators), 4)

        with self.subTest("Change qubit converter"):
            ucc.qubit_converter = QubitConverter(ParityMapper(),
                                                 two_qubit_reduction=True)
            # Has not been used to convert so we need to force it to do two qubit reduction
            ucc.qubit_converter.force_match(ucc.num_particles)
            self.assertIsNotNone(ucc.operators)
            self.assertEqual(ucc.num_qubits, 4)