cirq.contrib.graph_device.UndirectedGraphDevice

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A device whose properties are represented by an edge-labelled graph.

Inherits From: Device

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Main aliases

`cirq.contrib.graph_device.graph_device.UndirectedGraphDevice`

cirq.contrib.graph_device.UndirectedGraphDevice(
    device_graph: Optional[cirq.contrib.graph_device.UndirectedHypergraph] = None,
    crosstalk_graph: Optional[cirq.contrib.graph_device.UndirectedHypergraph] = None
) -> None

Each (undirected) edge of the device graph is labelled by an UndirectedGraphDeviceEdge or None. None indicates that any operation is allowed and has zero duration.

Each (undirected) edge of the constraint graph is labelled either by a function or None. The function takes as arguments operations on the adjacent device edges and raises an error if they are not simultaneously executable. If None, no such operations are allowed.

Note that

* the crosstalk graph is allowed to have vertices (i.e. device edges)
    that do not exist in the graph device.
* duration_of does not check that operation is valid.

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.

Attributes
edges
labelled_edges
qubits

Methods

can_add_operation_into_moment

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can_add_operation_into_moment(
    operation: "cirq.Operation",
    moment: "cirq.Moment"
) -> bool

Determines if it's possible to add an operation into a moment.

For example, on the XmonDevice two CZs shouldn't be placed in the same moment if they are on adjacent qubits.

Args
operation	The operation being added.
moment	The moment being transformed.

Returns
Whether or not the moment will validate after adding the operation.

decompose_operation

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decompose_operation(
    operation: "cirq.Operation"
) -> "cirq.OP_TREE"

Returns a device-valid decomposition for the given operation.

This method is used when adding operations into circuits with a device specified, to avoid spurious failures due to e.g. using a Hadamard gate that must be decomposed into native gates.

duration_of

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duration_of(
    operation: cirq.ops.Operation
) -> cirq.value.Duration

get_device_edge_from_op

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get_device_edge_from_op(
    operation: cirq.ops.Operation
) -> cirq.contrib.graph_device.graph_device.UndirectedGraphDeviceEdge

qid_pairs

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qid_pairs() -> FrozenSet['cirq.SymmetricalQidPair']

Returns a set of qubit edges on the device, if possible.

This property can be overridden in child classes for special handling. The default handling is: GridQids and LineQids will have neighbors as edges, and others will be fully connected.

Returns
If the device has a finite set of qubits, then a set of all edges on the device is returned. If the device has no well defined finite set of qubits (e.g. cirq.UnconstrainedDevice has this property), then None is returned.

qubit_set

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qubit_set() -> FrozenSet['cirq.Qid']

Returns a set or frozenset of qubits on the device, if possible.

Returns
If the device has a finite set of qubits, then a set or frozen set of all qubits on the device is returned. If the device has no well defined finite set of qubits (e.g. cirq.UnconstrainedDevice has this property), then None is returned.

validate_circuit

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validate_circuit(
    circuit: "cirq.AbstractCircuit"
) -> None

Raises an exception if a circuit is not valid.

Args
circuit	The circuit to validate.

Raises
ValueError	The circuit isn't valid for this device.

validate_crosstalk

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validate_crosstalk(
    operation: cirq.ops.Operation,
    other_operations: Iterable[cirq.ops.Operation]
) -> None

validate_moment

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validate_moment(
    moment: cirq.ops.Moment
)

Raises an exception if a moment is not valid.

Args
moment	The moment to validate.

Raises
ValueError	The moment isn't valid for this device.

validate_operation

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validate_operation(
    operation: cirq.ops.Operation
) -> None

Raises an exception if an operation is not valid.

Args
operation	The operation to validate.

Raises
ValueError	The operation isn't valid for this device.

__add__

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__add__(
    other
)

__eq__

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__eq__(
    other
)

Return self==value.