def simplify_circuit(circuit: 'cirq.Circuit') -> None:
"""Simplifies and optimizes the given circuit (in place).
Args:
circuit (cirq.Circuit): Circuit to simplify. Modified.
Currently it
* merges any neighboring gates belonging to the same one-parameter family
* merges all one-qubit rotations into phased X rotations followed by Z rotations
* pushes the Z rotations towards the end of the circuit as far as possible
* drops any empty Moments
"""
# the optimizers cause the immediate decomposition of any gates they insert into the Circuit
for _ in range(7):
# FIXME This sucks, but it seems that Cirq optimizers have no way of communicating
# if they actually made any changes to the Circuit, so we run a fixed number of iterations.
# Ideally we would keep doing this until the circuit hits a fixed point and no further changes are made.
# all mergeable 2-qubit gates are merged
MergeOneParameterGroupGates().optimize_circuit(circuit)
optimizers.merge_single_qubit_gates_into_phased_x_z(circuit)
# all z rotations are pushed past the first two-qubit gate following them
IQMEjectZ(eject_parameterized=True).optimize_circuit(circuit)
optimizers.DropEmptyMoments().optimize_circuit(circuit)
DropRZBeforeMeasurement().optimize_circuit(circuit)
optimizers.DropEmptyMoments().optimize_circuit(circuit)
DecomposeGatesFinal().optimize_circuit(circuit)
def _to_xmon_circuit(
self, circuit: circuits.Circuit, param_resolver: study.ParamResolver
) -> Tuple[circuits.Circuit, Set[str]]:
# TODO: Use one optimization pass.
xmon_circuit = protocols.resolve_parameters(circuit, param_resolver)
convert_to_xmon_gates.ConvertToXmonGates().optimize_circuit(
xmon_circuit)
optimizers.DropEmptyMoments().optimize_circuit(xmon_circuit)
keys = find_measurement_keys(xmon_circuit)
return xmon_circuit, keys
def program_as_schedule(self, program: TProgram) -> schedules.Schedule:
if isinstance(program, circuits.Circuit):
device = program.device
circuit_copy = program.copy()
optimizers.DropEmptyMoments().optimize_circuit(circuit_copy)
device.validate_circuit(circuit_copy)
return schedules.moment_by_moment_schedule(device, circuit_copy)
if isinstance(program, schedules.Schedule):
return program
raise TypeError('Unexpected program type.')
def program_as_schedule(
self, program: Union[circuits.Circuit, Schedule]) -> Schedule:
if isinstance(program, circuits.Circuit):
device = program.device
circuit_copy = program.copy()
ConvertToXmonGates().optimize_circuit(circuit_copy)
optimizers.DropEmptyMoments().optimize_circuit(circuit_copy)
device.validate_circuit(circuit_copy)
return moment_by_moment_schedule(device, circuit_copy)
if isinstance(program, Schedule):
return program
raise TypeError('Unexpected program type.')
def converted_gate_set(
circuit: circuits.Circuit,
no_clifford_gates: bool = False,
atol: float = 1e-8,
) -> circuits.Circuit:
"""Returns a new, equivalent circuit using the gate set
{SingleQubitCliffordGate,
CZ/PauliInteractionGate, PauliStringPhasor}.
"""
conv_circuit = circuits.Circuit(circuit)
optimizers.ConvertToCzAndSingleGates().optimize_circuit(conv_circuit)
optimizers.MergeSingleQubitGates().optimize_circuit(conv_circuit)
ConvertToPauliStringPhasors(
ignore_failures=True,
keep_clifford=not no_clifford_gates,
atol=atol,
).optimize_circuit(conv_circuit)
optimizers.DropEmptyMoments().optimize_circuit(conv_circuit)
return conv_circuit
