def is_valid_routing(
circuit: circuits.Circuit,
swap_network: SwapNetwork,
*,
equals: BINARY_OP_PREDICATE = operator.eq,
can_reorder: BINARY_OP_PREDICATE = circuits.circuit_dag._disjoint_qubits,
) -> bool:
"""Determines whether a swap network is consistent with a given circuit.
Args:
circuit: The circuit.
swap_network: The swap network whose validity is to be checked.
equals: The function to determine equality of operations. Defaults to
`operator.eq`.
can_reorder: A predicate that determines if two operations may be
reordered.
"""
circuit_dag = circuits.CircuitDag.from_circuit(circuit,
can_reorder=can_reorder)
logical_operations = swap_network.get_logical_operations()
try:
return cca.is_topologically_sorted(circuit_dag, logical_operations,
equals)
except ValueError as err:
if re.match(r'Operation .* acts on unmapped qubit .*\.', str(err)):
return False
raise
def test_topological_sort(circuit_dag, sorted_nodes):
sorted_nodes = list(sorted_nodes)
assert cca.is_topologically_sorted(circuit_dag,
(node.val for node in sorted_nodes))
assert not cca.is_topologically_sorted(circuit_dag,
(node.val
for node in sorted_nodes[:-1]))
assert not cca.is_topologically_sorted(
circuit_dag, (node.val for node in sorted_nodes + sorted_nodes[:2]))
v, w = next(iter(circuit_dag.edges))
i = sorted_nodes.index(v)
j = sorted_nodes.index(w, i + 1)
sorted_nodes[i], sorted_nodes[j] = sorted_nodes[j], sorted_nodes[j]
assert cca.is_topologically_sorted(
circuit_dag, (node.val for node in sorted_nodes)) == (v.val == w.val)