def can_add_operation_into_moment(self, operation: ops.Operation, moment: ops.Moment) -> bool:
"""
Determines if it's possible to add an operation into a moment. An
operation can be added if the moment with the operation added is valid
Args:
operation: The operation being added.
moment: The moment being transformed.
Returns:
Whether or not the moment will validate after adding the operation.
Raises:
ValueError: If either of the given moment or operation is invalid
"""
if not super().can_add_operation_into_moment(operation, moment):
return False
try:
self.validate_moment(moment.with_operation(operation))
except:
return False
return True
def _make_zeta_chi_gamma_compensation(
circuit_with_calibration: CircuitWithCalibration,
characterizations: List[PhasedFSimCalibrationResult],
gates_translator: Callable[[Gate], Optional[PhaseCalibratedFSimGate]],
permit_mixed_moments: bool,
) -> CircuitWithCalibration:
if permit_mixed_moments:
raise NotImplementedError(
'Mixed moments compensation ist supported yet')
if len(circuit_with_calibration.circuit) != len(
circuit_with_calibration.moment_to_calibration):
raise ValueError('Moment allocations does not match circuit length')
default_phases = PhasedFSimCharacterization(zeta=0.0, chi=0.0, gamma=0.0)
compensated = Circuit()
compensated_moment_to_calibration: List[Optional[int]] = []
for moment, characterization_index in zip(
circuit_with_calibration.circuit,
circuit_with_calibration.moment_to_calibration):
parameters = None
if characterization_index is not None:
parameters = characterizations[characterization_index]
decompositions: List[Tuple[Tuple[Operation, ...], ...]] = []
other: List[Operation] = []
new_moment_moment_to_calibration: Optional[List[Optional[int]]] = None
for op in moment:
if not isinstance(op, GateOperation):
raise IncompatibleMomentError(
'Moment contains operation different than GateOperation')
if isinstance(op.gate, _CALIBRATION_IRRELEVANT_GATES):
other.append(op)
continue
a, b = op.qubits
translated = gates_translator(op.gate)
if translated is None:
raise IncompatibleMomentError(
f'Moment {moment} contains unsupported non-single qubit operation {op}'
)
if parameters is None:
raise ValueError(
f'Missing characterization data for moment {moment}')
pair_parameters = parameters.get_parameters(a, b)
if pair_parameters is None:
raise ValueError(
f'Missing characterization data for pair {(a, b)} in {parameters}'
)
pair_parameters = pair_parameters.merge_with(default_phases)
corrections = FSimPhaseCorrections.from_characterization(
(a, b),
translated,
pair_parameters,
characterization_index,
)
decompositions.append(corrections.operations)
if new_moment_moment_to_calibration is None:
new_moment_moment_to_calibration = corrections.moment_to_calibration
else:
assert (
new_moment_moment_to_calibration ==
corrections.moment_to_calibration
), f'Inconsistent decompositions with a moment {moment}'
if other and decompositions:
raise IncompatibleMomentError(
f'Moment {moment} contains mixed operations')
elif other:
compensated += Moment(other)
compensated_moment_to_calibration.append(characterization_index)
elif decompositions:
for operations in itertools.zip_longest(*decompositions,
fillvalue=()):
compensated += Moment(operations)
assert new_moment_moment_to_calibration is not None # Required for mypy
compensated_moment_to_calibration += new_moment_moment_to_calibration
return CircuitWithCalibration(compensated,
compensated_moment_to_calibration)
def zeta_chi_gamma_calibration_for_moments(
circuit_with_calibration: CircuitWithCalibration,
characterizations: List[PhasedFSimCalibrationResult],
gates_translator: Callable[[Gate], Optional[FSimGate]] = try_convert_sqrt_iswap_to_fsim,
) -> CircuitWithCalibration:
"""Compensates circuit against errors in zeta, chi and gamma angles.
This method creates a new circuit with a single-qubit Z gates added in a such way so that
zeta, chi and gamma angles discovered by characterizations are cancelled-out and set to 0.
This function preserves a moment structure of the circuit. All single qubit gates appear on new
moments in the final circuit.
Args:
circuit_with_calibration: A CircuitWithCalibration (likely returned from run_calibrations)
whose mapping argument corresponds to the results in the characterizations argument.
characterizations: List of characterization results (likely returned from run_calibrations).
This should correspond to the circuit and mapping in the circuit_with_calibration
argument.
gates_translator: Function that translates a gate to a supported FSimGate which will undergo
characterization. Defaults to sqrt_iswap_gates_translator.
Returns:
Calibrated circuit together with its calibration metadata in CircuitWithCalibration object.
The calibrated circuit has single-qubit Z gates added which compensates for the true gates
imperfections.
The moment to calibration mapping is updated for the new circuit so that successive
calibrations could be applied.
"""
if len(circuit_with_calibration.circuit) != len(circuit_with_calibration.moment_to_calibration):
raise ValueError('Moment allocations does not match circuit length')
default_phases = PhasedFSimCharacterization(zeta=0.0, chi=0.0, gamma=0.0)
compensated = Circuit()
compensated_moment_to_calibration: List[Optional[int]] = []
for moment, characterization_index in zip(
circuit_with_calibration.circuit, circuit_with_calibration.moment_to_calibration
):
parameters = None
if characterization_index is not None:
parameters = characterizations[characterization_index]
decompositions: List[Tuple[Tuple[Operation, ...], ...]] = []
other: List[Operation] = []
new_moment_moment_to_calibration: Optional[List[Optional[int]]] = None
for op in moment:
if not isinstance(op, GateOperation):
raise IncompatibleMomentError(
'Moment contains operation different than GateOperation'
)
if isinstance(op.gate, (MeasurementGate, SingleQubitGate)):
other.append(op)
continue
a, b = op.qubits
translated_gate = gates_translator(op.gate)
if translated_gate is None:
raise IncompatibleMomentError(
f'Moment {moment} contains unsupported non-single qubit operation {op}'
)
if parameters is None:
raise ValueError(f'Missing characterization data for moment {moment}')
pair_parameters = parameters.get_parameters(a, b)
if pair_parameters is None:
raise ValueError(f'Missing characterization data for pair {(a, b)} in {parameters}')
pair_parameters = pair_parameters.merge_with(default_phases)
corrections = FSimPhaseCorrections.from_characterization(
(a, b), translated_gate, pair_parameters, characterization_index
)
decompositions.append(corrections.operations)
if new_moment_moment_to_calibration is None:
new_moment_moment_to_calibration = corrections.moment_to_calibration
else:
assert (
new_moment_moment_to_calibration == corrections.moment_to_calibration
), f'Inconsistent decompositions with a moment {moment}'
if other and decompositions:
raise IncompatibleMomentError(f'Moment {moment} contains mixed operations')
elif other:
compensated += Moment(other)
compensated_moment_to_calibration.append(characterization_index)
elif decompositions:
for operations in zip_longest(*decompositions, fillvalue=()):
compensated += Moment(operations)
assert new_moment_moment_to_calibration is not None # Required for mypy
compensated_moment_to_calibration += new_moment_moment_to_calibration
return CircuitWithCalibration(compensated, compensated_moment_to_calibration)
