qiskit.dagcircuit.DAGNode

class DAGNode(type=None, op=None, name=None, qargs=None, cargs=None, wire=None, nid=- 1)

Object to represent the information at a node in the DAGCircuit.

It is used as the return value from *_nodes() functions and can be supplied to functions that take a node.

Create a node

__init__(type=None, op=None, name=None, qargs=None, cargs=None, wire=None, nid=- 1)

Create a node

Methods

__init__([type, op, name, qargs, cargs, …])	Create a node
semantic_eq(node1, node2[, bit_indices1, …])	Check if DAG nodes are considered equivalent, e.g., as a node_match for nx.is_isomorphic.

Attributes

cargs
condition	Returns the condition of the node.op
name	Returns the Instruction name corresponding to the op for this node
op	Returns the Instruction object corresponding to the op for the node, else None
qargs	Returns list of Qubit, else an empty list.
sort_key
type
wire	Returns the Bit object, else None.

property condition

Returns the condition of the node.op

property name

Returns the Instruction name corresponding to the op for this node

property op

Returns the Instruction object corresponding to the op for the node, else None

property qargs

Returns list of Qubit, else an empty list.

static semantic_eq(node1, node2, bit_indices1=None, bit_indices2=None)

Check if DAG nodes are considered equivalent, e.g., as a node_match for nx.is_isomorphic.

Parameters

• node1 (DAGNode) – A node to compare.

• node2 (DAGNode) – The other node to compare.

• bit_indices1 (dict) – Dictionary mapping Bit instances to their index within the circuit containing node1

• bit_indices2 (dict) – Dictionary mapping Bit instances to their index within the circuit containing node2

Returns

If node1 == node2

Return type

Bool

property wire

Returns the Bit object, else None.