Source code for qiskit.dagcircuit.dagdepnode

# This code is part of Qiskit.
# (C) Copyright IBM 2020.
# This code is licensed under the Apache License, Version 2.0. You may
# obtain a copy of this license in the LICENSE.txt file in the root directory
# of this source tree or at
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.

# pylint: disable=redefined-builtin

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

from qiskit.exceptions import QiskitError

[docs]class DAGDepNode: """Object to represent the information at a node in the DAGDependency(). It is used as the return value from `*_nodes()` functions and can be supplied to functions that take a node. """ __slots__ = [ "type", "_op", "name", "_qargs", "cargs", "sort_key", "node_id", "successors", "predecessors", "reachable", "matchedwith", "isblocked", "successorstovisit", "qindices", "cindices", ] def __init__( self, type=None, op=None, name=None, qargs=(), cargs=(), successors=None, predecessors=None, reachable=None, matchedwith=None, successorstovisit=None, isblocked=None, qindices=None, cindices=None, nid=-1, ): self.type = type self._op = op = name self._qargs = tuple(qargs) if qargs is not None else () self.cargs = tuple(cargs) if cargs is not None else () self.node_id = nid self.sort_key = str(self._qargs) self.successors = successors if successors is not None else [] self.predecessors = predecessors if predecessors is not None else [] self.reachable = reachable self.matchedwith = matchedwith if matchedwith is not None else [] self.isblocked = isblocked self.successorstovisit = successorstovisit if successorstovisit is not None else [] self.qindices = qindices if qindices is not None else [] self.cindices = cindices if cindices is not None else [] @property def op(self): """Returns the Instruction object corresponding to the op for the node, else None""" if not self.type or self.type != "op": raise QiskitError("The node %s is not an op node" % (str(self))) return self._op @op.setter def op(self, data): self._op = data @property def qargs(self): """ Returns list of Qubit, else an empty list. """ return self._qargs @qargs.setter def qargs(self, new_qargs): """Sets the qargs to be the given list of qargs.""" self._qargs = tuple(new_qargs) self.sort_key = str(new_qargs)
[docs] @staticmethod def semantic_eq(node1, node2): """ Check if DAG nodes are considered equivalent, e.g., as a node_match for nx.is_isomorphic. Args: node1 (DAGDepNode): A node to compare. node2 (DAGDepNode): The other node to compare. Return: Bool: If node1 == node2 """ # For barriers, qarg order is not significant so compare as sets if "barrier" == == return set(node1._qargs) == set(node2._qargs) if node1.type == node2.type: if node1._op == node2._op: if == if node1._qargs == node2._qargs: if node1.cargs == node2.cargs: if node1.type == "op": if getattr(node1._op, "condition", None) != getattr( node2._op, "condition", None ): return False return True return False
[docs] def copy(self): """ Function to copy a DAGDepNode object. Returns: DAGDepNode: a copy of a DAGDepNode object. """ dagdepnode = DAGDepNode() dagdepnode.type = self.type dagdepnode._op = self.op = dagdepnode._qargs = self._qargs dagdepnode.cargs = self.cargs dagdepnode.node_id = self.node_id dagdepnode.sort_key = self.sort_key dagdepnode.successors = self.successors dagdepnode.predecessors = self.predecessors dagdepnode.reachable = self.reachable dagdepnode.isblocked = self.isblocked dagdepnode.successorstovisit = self.successorstovisit dagdepnode.qindices = self.qindices dagdepnode.cindices = self.cindices dagdepnode.matchedwith = self.matchedwith.copy() return dagdepnode