def test_swap_network_gate_from_ops():
n_qubits = 10
qubits = cirq.LineQubit.range(n_qubits)
part_lens = (1, 2, 1, 3, 3)
operations = [
cirq.Z(qubits[0]),
cirq.CZ(*qubits[1:3]),
cirq.CCZ(*qubits[4:7]),
cirq.CCZ(*qubits[7:])
]
acquaintance_size = 3
swap_network = SwapNetworkGate.from_operations(qubits, operations,
acquaintance_size)
assert swap_network.acquaintance_size == acquaintance_size
assert swap_network.part_lens == part_lens
def replace_acquaintance_with_swap_network(
circuit: 'cirq.Circuit',
qubit_order: Sequence['cirq.Qid'],
acquaintance_size: Optional[int] = 0,
swap_gate: 'cirq.Gate' = ops.SWAP,
) -> bool:
"""
Replace every moment containing acquaintance gates (after
rectification) with a generalized swap network, with the partition
given by the acquaintance gates in that moment (and singletons for the
free qubits). Accounts for reversing effect of swap networks.
Args:
circuit: The acquaintance strategy.
qubit_order: The qubits, in order, on which the replacing swap network
gate acts on.
acquaintance_size: The acquaintance size of the new swap network gate.
swap_gate: The gate used to swap logical indices.
Returns: Whether or not the overall effect of the inserted swap network
gates is to reverse the order of the qubits, i.e. the parity of the
number of swap network gates inserted.
Raises:
TypeError: circuit is not an acquaintance strategy.
"""
if not is_acquaintance_strategy(circuit):
raise TypeError('not is_acquaintance_strategy(circuit)')
rectify_acquaintance_strategy(circuit)
reflected = False
reverse_map = {q: r for q, r in zip(qubit_order, reversed(qubit_order))}
for moment_index, moment in enumerate(circuit):
if reflected:
moment = moment.transform_qubits(reverse_map.__getitem__)
if all(
isinstance(op.gate, AcquaintanceOpportunityGate)
for op in moment.operations):
swap_network_gate = SwapNetworkGate.from_operations(
qubit_order, moment.operations, acquaintance_size, swap_gate)
swap_network_op = swap_network_gate(*qubit_order)
moment = ops.Moment([swap_network_op])
reflected = not reflected
circuit._moments[moment_index] = moment
return reflected