C贸digo fuente para qiskit.transpiler.passes.optimization.reset_after_measure_simplification

# This code is part of Qiskit.
# (C) Copyright IBM 2017, 2021.
# 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 http://www.apache.org/licenses/LICENSE-2.0.
# 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.

"""Replace resets after measure with a conditional XGate."""

from qiskit.transpiler.basepasses import TransformationPass
from qiskit.transpiler.passes.utils import control_flow
from qiskit.circuit.library.standard_gates.x import XGate
from qiskit.circuit.reset import Reset
from qiskit.circuit.measure import Measure
from qiskit.dagcircuit.dagcircuit import DAGCircuit
from qiskit.dagcircuit.dagnode import DAGOpNode

[documentos]class ResetAfterMeasureSimplification(TransformationPass): """This pass replaces reset after measure with a conditional X gate. This optimization is suitable for use on IBM Quantum systems where the reset operation is performed by a measurement followed by a conditional x-gate. It might not be desireable on other backends if reset is implemented differently. """
[documentos] @control_flow.trivial_recurse def run(self, dag): """Run the pass on a dag.""" for node in dag.op_nodes(Measure): succ = next(dag.quantum_successors(node)) if isinstance(succ, DAGOpNode) and isinstance(succ.op, Reset): new_x = XGate() new_x.condition = (node.cargs[0], 1) new_dag = DAGCircuit() new_dag.add_qubits(node.qargs) new_dag.add_clbits(node.cargs) new_dag.apply_operation_back(node.op, node.qargs, node.cargs) new_dag.apply_operation_back(new_x, node.qargs) dag.remove_op_node(succ) dag.substitute_node_with_dag(node, new_dag) return dag