def __init__(
self,
device_graph: Optional[UndirectedHypergraph] = None,
crosstalk_graph: Optional[UndirectedHypergraph] = None,
) -> None:
"""Inits UndirectedGraphDevice.
Args:
device_graph: An undirected hypergraph whose vertices correspond to
qubits and whose edges determine allowable operations and their
durations.
crosstalk_graph: An undirected hypergraph whose vertices are edges
of device_graph and whose edges give simultaneity constraints
thereon.
Raises:
TypeError: If the crosstalk graph is not a valid crosstalk graph.
"""
if device_graph is None:
device_graph = UndirectedHypergraph()
if not is_undirected_device_graph(device_graph):
raise TypeError(f'not is_undirected_device_graph({device_graph})')
if crosstalk_graph is None:
crosstalk_graph = UndirectedHypergraph()
if not is_crosstalk_graph(crosstalk_graph):
raise TypeError(f'not is_crosstalk_graph({crosstalk_graph})')
self.device_graph = device_graph
self.crosstalk_graph = crosstalk_graph
def uniform_undirected_graph_device(
edges: Iterable[Iterable[ops.Qid]],
edge_label: Optional[UndirectedGraphDeviceEdge] = None
) -> UndirectedGraphDevice:
"""An undirected graph device all of whose edges are the same.
Args:
edges: The edges.
edge_label: The label to apply to all edges. Defaults to None.
"""
labelled_edges = {frozenset(edge): edge_label
for edge in edges} # type: Dict[Iterable[Hashable], Any]
device_graph = UndirectedHypergraph(labelled_edges=labelled_edges)
return UndirectedGraphDevice(device_graph=device_graph)