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

# This code is part of Qiskit.
#
# (C) Copyright IBM 2017, 2018.
#
# 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 a property reached a fixed point."""

from copy import deepcopy

from qiskit.transpiler.basepasses import AnalysisPass

[ドキュメント]class FixedPoint(AnalysisPass):
"""Check if a property reached a fixed point.

A dummy analysis pass that checks if a property reached a fixed point.
The results is saved in property_set['<property>_fixed_point']
as a boolean.
"""

[ドキュメント]    def __init__(self, property_to_check):
"""FixedPoint initializer.

Args:
property_to_check (str): The property to check if a fixed point was reached.
"""
super().__init__()
self._property = property_to_check

[ドキュメント]    def run(self, dag):
"""Run the FixedPoint pass on dag."""
current_value = self.property_set[self._property]
fixed_point_previous_property = '_fixed_point_previous_%s' % self._property

if self.property_set[fixed_point_previous_property] is None:
self.property_set['%s_fixed_point' % self._property] = False
else:
fixed_point_reached = self.property_set[fixed_point_previous_property] == current_value
self.property_set['%s_fixed_point' % self._property] = fixed_point_reached

self.property_set[fixed_point_previous_property] = deepcopy(current_value)