C贸digo fuente para qiskit.transpiler.passes.scheduling.padding.pad_delay

# This code is part of Qiskit.
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# (C) Copyright IBM 2022.
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# 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
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"""Padding pass to insert Delay to the empty slots."""

from qiskit.circuit import Qubit
from qiskit.circuit.delay import Delay
from qiskit.dagcircuit import DAGCircuit, DAGNode, DAGOutNode
from qiskit.transpiler.target import Target

from .base_padding import BasePadding


[documentos]class PadDelay(BasePadding): """Padding idle time with Delay instructions. Consecutive delays will be merged in the output of this pass. .. code-block:: python durations = InstructionDurations([("x", None, 160), ("cx", None, 800)]) qc = QuantumCircuit(2) qc.delay(100, 0) qc.x(1) qc.cx(0, 1) The ASAP-scheduled circuit output may become .. parsed-literal:: 鈹屸攢鈹鈹鈹鈹鈹鈹鈹鈹鈹鈹鈹鈹鈹鈹鈹鈹 q_0: 鈹 Delay(160[dt]) 鈹溾攢鈹鈻犫攢鈹 鈹斺攢鈹鈹鈹鈹鈹攢鈹鈹鈹攢鈹鈹鈹鈹鈹鈹樷攲鈹鈹粹攢鈹 q_1: 鈹鈹鈹鈹鈹鈹鈹 X 鈹溾攢鈹鈹鈹鈹鈹鈹鈹 X 鈹 鈹斺攢鈹鈹鈹 鈹斺攢鈹鈹鈹 Note that the additional idle time of 60dt on the ``q_0`` wire coming from the duration difference between ``Delay`` of 100dt (``q_0``) and ``XGate`` of 160 dt (``q_1``) is absorbed in the delay instruction on the ``q_0`` wire, i.e. in total 160 dt. See :class:`BasePadding` pass for details. """ def __init__(self, fill_very_end: bool = True, target: Target = None): """Create new padding delay pass. Args: fill_very_end: Set ``True`` to fill the end of circuit with delay. target: The :class:`~.Target` representing the target backend. If it supplied and it does not support delay instruction on a qubit, padding passes do not pad any idle time of the qubit. """ super().__init__(target=target) self.fill_very_end = fill_very_end def _pad( self, dag: DAGCircuit, qubit: Qubit, t_start: int, t_end: int, next_node: DAGNode, prev_node: DAGNode, ): if not self.fill_very_end and isinstance(next_node, DAGOutNode): return time_interval = t_end - t_start self._apply_scheduled_op(dag, t_start, Delay(time_interval, dag.unit), qubit)