def test_get_context_selection_circuit_for_group(self):
group = QubitOperator(((0, "X"), (1, "Y"))) - 0.5 * QubitOperator(
((1, "Y"), ))
circuit, ising_operator = get_context_selection_circuit_for_group(
group)
# Need to convert to QubitOperator in order to get matrix representation
qubit_operator = QubitOperator()
for ising_term in ising_operator.terms:
qubit_operator += QubitOperator(ising_term,
ising_operator.terms[ising_term])
target_unitary = qubit_operator_sparse(group)
transformed_unitary = (
circuit.to_unitary().conj().T
@ qubit_operator_sparse(qubit_operator) @ circuit.to_unitary())
self.assertTrue(
np.allclose(target_unitary.todense(), transformed_unitary))
def test_group_greedily_all_comeasureable(self):
target_operator = 10.0 * QubitOperator("Y0")
target_operator -= 3.0 * QubitOperator("Y0 Y1")
target_operator += 1.0 * QubitOperator("Y1")
target_operator += 20.0 * QubitOperator("Y0 Y1 Y2")
circuit = Circuit([X(0), X(1), X(2)])
estimation_tasks = [EstimationTask(target_operator, circuit, None)]
grouped_tasks = group_greedily(estimation_tasks)
assert len(grouped_tasks) == 1
assert grouped_tasks[0].operator == target_operator
for initial_task, modified_task in zip(estimation_tasks,
grouped_tasks):
assert modified_task.circuit == initial_task.circuit
assert modified_task.number_of_shots == initial_task.number_of_shots
def generate_qubitop(P):
#Converts Pauli representation used in gradient grouping algorithm to QubitOperator.
pauli_str = ''
for c in range(0, len(P)):
if P[c] != 'e':
pauli_str += P[c].upper() + str(c) + ' '
return QubitOperator(pauli_str)
def test_build_qaoa_circuit(self):
# Given
hamiltonian_1 = QubitOperator('Z0')
hamiltonian_2 = QubitOperator('X0')
hamiltonians = [hamiltonian_1, hamiltonian_2]
params = np.array([1, 1])
pyquil_prog = pyquil.quil.Program().inst(pyquil.gates.H(0),
pyquil.gates.RZ(2.0, 0),
pyquil.gates.H(0),
pyquil.gates.RZ(2.0, 0),
pyquil.gates.H(0))
correct_circuit = Circuit(pyquil_prog)
# When
circuit = build_qaoa_circuit(params, hamiltonians)
# Then
self.assertEqual(circuit, correct_circuit)
def test_qubitop_to_paulisum_identity_operator(self):
# Given
qubit_operator = QubitOperator("", 4)
# When
paulisum = qubitop_to_paulisum(qubit_operator)
# Then
self.assertEqual(paulisum.qubits, ())
self.assertEqual(paulisum, PauliSum() + 4)
def test_qubit_operator_io(self):
# Given
qubit_op = QubitOperator(((0, "Y"), (3, "X"), (8, "Z"), (11, "X")),
3.0j)
# When
save_qubit_operator(qubit_op, "qubit_op.json")
loaded_op = load_qubit_operator("qubit_op.json")
# Then
self.assertEqual(qubit_op, loaded_op)
def test_get_estimated_expectation_values_with_constant(self):
for estimator in self.estimators:
# Given
coefficient = -2
constant_qubit_operator = QubitOperator(
(), coefficient) + QubitOperator((0, "X"))
# When
values = estimator.get_estimated_expectation_values(
self.backend,
self.circuit,
constant_qubit_operator,
n_samples=self.n_samples,
epsilon=self.epsilon,
delta=self.delta,
).values
value = values[1]
# Then
self.assertTrue(len(values) == 2)
self.assertEqual(coefficient, value)
def test_single_mode_projection(self):
"""Find the coeffcient of a wavefunction generated from a single qubit.
"""
n_qubits = 1
qubits = cirq.LineQubit.range(n_qubits)
ops = QubitOperator('X0', 1.0)
init_state = numpy.zeros(2**n_qubits, dtype=numpy.complex128)
init_state[1] = 1.0 + 0.0j
cof = numpy.zeros(n_qubits, dtype=numpy.complex128)
cirq_utils.qubit_projection(ops, qubits, init_state, cof)
self.assertEqual(cof[0], 1.0 + 0.0j)
def test_build_qubitoperator_from_coeffs_and_labels(self):
# Given
test_op = QubitOperator(((0, "Y"), (1, "X"), (2, "Z"), (4, "X")), 3.0j)
coeffs = [3.0j]
labels = [[2, 1, 3, 0, 1]]
# When
build_op = get_qubitop_from_coeffs_and_labels(coeffs, labels)
# Then
self.assertEqual(test_op, build_op)
def test_get_exact_expectation_values_empty_op(self, wf_simulator):
# Given
circuit = Circuit(Program(H(0), CNOT(0, 1), CNOT(1, 2)))
qubit_operator = QubitOperator()
target_value = 0.0
# When
expectation_values = wf_simulator.get_exact_expectation_values(
circuit, qubit_operator
)
# Then
assert sum(expectation_values.values) == pytest.approx(target_value, abs=1e-7)
def test_types_consistency():
r"""Test the type consistency of the qubit Hamiltonian constructed by 'convert_observable' from
an OpenFermion QubitOperator with respect to the same observable built directly using PennyLane
operations"""
# Reference PL operator
pl_ref = 1 * qml.Identity(0) + 2 * qml.PauliZ(0) @ qml.PauliX(1)
# Corresponding OpenFermion QubitOperator
of = QubitOperator("", 1) + QubitOperator("Z0 X1", 2)
# Build PL operator using 'convert_observable'
pl = qchem.convert_observable(of)
ops = pl.terms[1]
ops_ref = pl_ref.terms[1]
for i, op in enumerate(ops):
assert op.name == ops_ref[i].name
assert type(op) == type(ops_ref[i])
def test_qubitop_io(self):
# Given
qubit_op = QubitOperator(((0, 'Y'), (1, 'X'), (2, 'Z'), (4, 'X')), 3.j)
# When
save_qubit_operator(qubit_op, 'qubit_op.json')
loaded_op = load_qubit_operator('qubit_op.json')
# Then
self.assertEqual(qubit_op, loaded_op)
os.remove('qubit_op.json')
def test_qubitop_to_dict_io(self):
# Given
qubit_op = QubitOperator(((0, 'Y'), (1, 'X'), (2, 'Z'), (4, 'X')), 3.j)
qubit_op += hermitian_conjugated(qubit_op)
# When
qubitop_dict = convert_qubitop_to_dict(qubit_op)
recreated_qubit_op = convert_dict_to_qubitop(qubitop_dict)
# Then
self.assertEqual(recreated_qubit_op, qubit_op)
def test_listupCSFs(self):
from openfermion import QubitOperator, commutator
ZZZZ = QubitOperator('Z0 Z1 Z2 Z3')
ZZZZ2 = QubitOperator('Z0 Z1 Z4 Z6')
from freqerica.op.symm import SymmRemover
norb = 4
n_qubit = norb * 2
remover = SymmRemover(n_qubit, [ZZZZ, ZZZZ2])
print(remover)
remover.set_eigvals([-1, +1])
print(remover)
wfs = freqerica.op.util.listupCSFs(norb,
mult=1,
na=2,
nb=2,
remover=remover)
#print(wfs)
assert True
def __init__(self,
qubit_operator: typing.Union[QubitOperator, str,
numbers.Number] = None):
"""
Initialize from string or from a preexisting OpenFermion QubitOperator instance
:param qubit_operator: string or openfermion.QubitOperator
if string: Same conventions as openfermion
if None: The Hamiltonian is initialized as identity operator
if Number: initialized as scaled unit operator
"""
if isinstance(qubit_operator, str):
self._qubit_operator = self.from_string(
string=qubit_operator)._qubit_operator
elif qubit_operator is None:
self._qubit_operator = QubitOperator.zero()
elif isinstance(qubit_operator, numbers.Number):
self._qubit_operator = qubit_operator * QubitOperator.identity()
else:
self._qubit_operator = qubit_operator
assert (isinstance(self._qubit_operator, QubitOperator))
def test_get_context_selection_circuit_offdiagonal(self):
term = QubitOperator("X0 Y1")
circuit, ising_operator = get_context_selection_circuit(term)
# Need to convert to QubitOperator in order to get matrix representation
qubit_operator = change_operator_type(ising_operator, QubitOperator)
target_unitary = qubit_operator_sparse(term)
transformed_unitary = (
circuit.to_unitary().conj().T
@ qubit_operator_sparse(qubit_operator) @ circuit.to_unitary())
assert np.allclose(target_unitary.todense(), transformed_unitary)
def test_get_exact_expectation_values_empty_op(self):
# Given
circuit = Circuit(Program(H(0), CNOT(0, 1), CNOT(1, 2)))
qubit_operator = QubitOperator()
target_value = 0.0
# When
for simulator in self.wf_simulators:
expectation_values = simulator.get_exact_expectation_values(
circuit, qubit_operator)
# Then
self.assertAlmostEqual(sum(expectation_values.values),
target_value)
def get_maxcut_hamiltonian(graph,
scaling=1.0,
shifted=False,
l1_normalized=False):
"""Converts a MAXCUT instance, as described by a weighted graph, to an Ising
Hamiltonian. It allows for different convention in the choice of the
Hamiltonian.
Args:
graph (networkx.Graph): undirected weighted graph describing the MAXCUT
instance.
scaling (float): scaling of the terms of the Hamiltonian
shifted (bool): if True include a shift. Default: False
l1_normalized (bool): normalize the operator using the l1_norm = \sum |w|
Returns:
zquantum.core.qubitoperator.QubitOperator object describing the
Hamiltonian
H = \sum_{<i,j>} w_{i,j} * scaling * (Z_i Z_j - shifted * I)
or H_norm = H / l1_norm if l1_normalized is True.
"""
output = QubitOperator()
nodes_dict = generate_graph_node_dict(graph)
l1_norm = 0
for edge in graph.edges:
coeff = graph.edges[edge[0], edge[1]]["weight"] * scaling
l1_norm += np.abs(coeff)
node_index1 = nodes_dict[edge[0]]
node_index2 = nodes_dict[edge[1]]
ZZ_term_str = "Z" + str(node_index1) + " Z" + str(node_index2)
output += QubitOperator(ZZ_term_str, coeff)
if shifted:
output += QubitOperator("", -coeff) # constant term, i.e I
if l1_normalized and (l1_norm > 0):
output /= l1_norm
return output
def symmetry_pauli_string(orbprop, operation_list):
operation_paulistr_table = {}
na = QubitOperator(())
nb = QubitOperator(())
for i in range(orbprop.ncas):
na *= QubitOperator((i * 2, 'Z'))
nb *= QubitOperator((i * 2 + 1, 'Z'))
if 'na' in operation_list: operation_paulistr_table['na'] = na
if 'nb' in operation_list: operation_paulistr_table['nb'] = nb
ncore, ncas = orbprop.ncore, orbprop.ncas
for op in operation_list:
if op == 'na' or op == 'nb': continue
qop_paulistr = QubitOperator(())
for i, iorb in enumerate(range(ncore, ncore + ncas)):
irrep = orbprop.irreps[iorb]
char = symmtable[irrep][op]
if char == -1:
qop_paulistr *= QubitOperator([(i * 2, 'Z'), (i * 2 + 1, 'Z')])
if char == NA:
qop_paulistr = None
break
if qop_paulistr is not None:
operation_paulistr_table[op] = qop_paulistr
return operation_paulistr_table
def get_qubitop_from_coeffs_and_labels(
coeffs: List[float], labels: List[List[int]]
) -> QubitOperator:
"""Generates a QubitOperator based on a coefficient vector and
a label matrix.
Args:
coeffs: a list of floats representing the coefficients
for the terms in the Hamiltonian
labels: a list of lists (a matrix) where each list
is a vector of integers representing the Pauli
string. See pauliutil.py for details.
Example:
The Hamiltonian H = 0.1 X1 X2 - 0.4 Y1 Y2 Z3 Z4 can be
initiated by calling
H = QubitOperator([0.1, -0.4],\ # coefficients
[[1 1 0 0],\ # label matrix
[2 2 3 3]])
"""
output = QubitOperator()
for i in range(0, len(labels)):
string_term = ""
for ind, elem in enumerate(labels[i]):
pauli_symbol = ""
if elem == 1:
pauli_symbol = "X" + str(ind) + " "
if elem == 2:
pauli_symbol = "Y" + str(ind) + " "
if elem == 3:
pauli_symbol = "Z" + str(ind) + " "
string_term += pauli_symbol
output += coeffs[i] * QubitOperator(string_term)
return output
def ansatz_based_cost_function():
target_operator = QubitOperator("Z0")
ansatz = MockAnsatz(number_of_layers=1, problem_size=1)
backend = MockQuantumSimulator()
estimation_method = estimate_expectation_values_by_averaging
estimation_preprocessors = [partial(allocate_shots_uniformly, number_of_shots=1)]
return AnsatzBasedCostFunction(
target_operator,
ansatz,
backend,
estimation_method=estimation_method,
estimation_preprocessors=estimation_preprocessors,
)
def test_one_qubit_parametric_gates_using_expectation_values(
self, backend_for_gates_test, initial_gate, tested_gate, params,
target_values):
if backend_for_gates_test.n_samples is None:
pytest.xfail(
"This test won't work for simulators without sampling, it's covered by "
"a test in QuantumSimulatorTests.")
# Given
qubit_list = [Qubit(0)]
gate_1 = Gate(initial_gate, qubits=qubit_list)
gate_2 = Gate(tested_gate, params=params, qubits=qubit_list)
circuit = Circuit()
circuit.qubits = qubit_list
circuit.gates = [gate_1, gate_2]
operators = [
QubitOperator("[]"),
QubitOperator("[X0]"),
QubitOperator("[Y0]"),
QubitOperator("[Z0]"),
]
sigma = 1 / np.sqrt(backend_for_gates_test.n_samples)
for i, operator in enumerate(operators):
# When
estimation_tasks = [
EstimationTask(operator, circuit,
backend_for_gates_test.n_samples)
]
expectation_values = estimate_expectation_values_by_averaging(
backend_for_gates_test, estimation_tasks)
calculated_value = expectation_values.values[0]
# Then
assert calculated_value == pytest.approx(target_values[i],
abs=sigma * 3)
def noisy_ansatz():
target_operator = QubitOperator("Z0")
ansatz = MockAnsatz(number_of_layers=2, problem_size=1)
backend = MockQuantumSimulator()
estimator = MockEstimator()
ansatz.get_executable_circuit = mock.Mock(
wraps=ansatz.get_executable_circuit)
return AnsatzBasedCostFunction(target_operator,
ansatz,
backend,
estimator=estimator,
parameter_precision=1e-4,
parameter_precision_seed=1234)
def test_compute_group_variances_without_ref(groups, expecval):
test_variances = compute_group_variances(groups, expecval)
test_ham_variance = np.sum(test_variances)
# Assemble H and compute its variances independently
ham = QubitOperator()
for g in groups:
ham += g
ham_coeff = np.array(list(ham.terms.values()))
pauli_var = 1.0 - expecval.values**2
ref_ham_variance = np.sum(ham_coeff**2 * pauli_var)
assert math.isclose(
test_ham_variance,
ref_ham_variance) # this is true as long as the groups do not overlap
def test_get_exact_expectation_values(self):
# Given
circuit = Circuit(Program(H(0), CNOT(0, 1), CNOT(1, 2)))
qubit_operator = QubitOperator('2[] - [Z0 Z1] + [X0 X2]')
target_values = np.array([2., -1., 0.])
# When
for simulator in self.wf_simulators:
expectation_values = simulator.get_exact_expectation_values(
circuit, qubit_operator)
# Then
np.testing.assert_array_almost_equal(expectation_values.values,
target_values)
def test_qubit_wavefunction_from_vacuum(self):
"""Build a wavefunction given a group of qubit operations.
"""
test_val = 1.0 + 2.0 + 3.0 + 5.0 + 7.0 + 11.0 + 13.0 + 0.j
n_qubits = 1
qubits = cirq.LineQubit.range(n_qubits)
ops = QubitOperator('X0', 1.0) + QubitOperator('X0', 2.0) \
+ QubitOperator('X0', 3.0) + QubitOperator('X0', 5.0) \
+ QubitOperator('X0', 7.0) + QubitOperator('X0', 11.0) \
+ QubitOperator('X0', 13.0)
state = cirq_utils.qubit_wavefunction_from_vacuum(ops, qubits)
self.assertEqual(state[1], test_val)
def test_one_qubit_non_parametric_gates_using_expectation_values(
self, backend_for_gates_test, initial_gate, tested_gate,
target_values):
if backend_for_gates_test.n_samples is None:
pytest.xfail(
"This test won't work for simulators without sampling, it should be covered by a test in QuantumSimulatorTests."
)
# Given
qubit_list = [Qubit(0)]
gate_1 = Gate(initial_gate, qubits=qubit_list)
gate_2 = Gate(tested_gate, qubits=qubit_list)
circuit = Circuit()
circuit.qubits = qubit_list
circuit.gates = [gate_1, gate_2]
operators = [
QubitOperator("[]"),
QubitOperator("[X0]"),
QubitOperator("[Y0]"),
QubitOperator("[Z0]"),
]
sigma = 1 / np.sqrt(backend_for_gates_test.n_samples)
for i, operator in enumerate(operators):
# When
estimator = BasicEstimator()
expectation_value = estimator.get_estimated_expectation_values(
backend_for_gates_test,
circuit,
operator,
).values[0]
# Then
assert expectation_value == pytest.approx(target_values[i],
abs=sigma * 3)
def test_qubitop_to_paulisum_setting_qubits(self):
# Given
qubit_operator = QubitOperator("Z0 Z1", -1.5)
expected_qubits = (LineQubit(0), LineQubit(5))
expected_paulisum = (PauliSum() +
PauliString(Z.on(expected_qubits[0])) *
PauliString(Z.on(expected_qubits[1])) * -1.5)
# When
paulisum = qubitop_to_paulisum(qubit_operator, qubits=expected_qubits)
# Then
self.assertEqual(paulisum.qubits, expected_qubits)
self.assertEqual(paulisum, expected_paulisum)
def test_qubitop_to_paulisum_z0z1_operator(self):
# Given
qubit_operator = QubitOperator("Z0 Z1", -1.5)
expected_qubits = (GridQubit(0, 0), GridQubit(1, 0))
expected_paulisum = (PauliSum() +
PauliString(Z.on(expected_qubits[0])) *
PauliString(Z.on(expected_qubits[1])) * -1.5)
# When
paulisum = qubitop_to_paulisum(qubit_operator)
# Then
self.assertEqual(paulisum.qubits, expected_qubits)
self.assertEqual(paulisum, expected_paulisum)
def taper_qubits_off(self, qop):
indices_targetpauli = {
util.paulistr(qop_tgtpauli)[0][0]
for qop_tgtpauli in self.targetpauli_qop_list
}
index_pack_map = []
index_new = 0
for index_old in range(self.n_qubit):
if index_old in indices_targetpauli:
index_pack_map.append(None)
else:
index_pack_map.append(index_new)
index_new += 1
qop_tapered = QubitOperator()
for pauli_string, coeff in qop.terms.items():
pauli_string_new = []
for index_old, axis in pauli_string:
index_new = index_pack_map[index_old]
pauli_string_new.append((index_new, axis))
qop_tapered += QubitOperator(pauli_string_new, coeff)
return qop_tapered