# qiskit.transpiler.passes.utils.dag_fixed_point のソースコード

# This code is part of Qiskit.
#
# (C) Copyright IBM 2017, 2019.
#
# obtain a copy of this license in the LICENSE.txt file in the root directory
#
# 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.

"""Check if the DAG has reached a fixed point."""

from copy import deepcopy

from qiskit.transpiler.basepasses import AnalysisPass

[ドキュメント]class DAGFixedPoint(AnalysisPass):
"""Check if the DAG has reached a fixed point.

A dummy analysis pass that checks if the DAG a fixed point (the DAG is not
modified anymore). The results is saved in
property_set['dag_fixed_point'] as a boolean.
"""

[ドキュメント]    def run(self, dag):
"""Run the DAGFixedPoint pass on dag."""
if self.property_set['_dag_fixed_point_previous_dag'] is None:
self.property_set['dag_fixed_point'] = False
else:
fixed_point_reached = self.property_set['_dag_fixed_point_previous_dag'] == dag
self.property_set['dag_fixed_point'] = fixed_point_reached

self.property_set['_dag_fixed_point_previous_dag'] = deepcopy(dag)