Quellcode für qiskit.converters.circuit_to_dag

# This code is part of Qiskit.
# (C) Copyright IBM 2017, 2018.
# 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.

"""Helper function for converting a circuit to a dag"""
import copy

from qiskit.dagcircuit.dagcircuit import DAGCircuit

[Doku]def circuit_to_dag(circuit, copy_operations=True, *, qubit_order=None, clbit_order=None): """Build a :class:`.DAGCircuit` object from a :class:`.QuantumCircuit`. Args: circuit (QuantumCircuit): the input circuit. copy_operations (bool): Deep copy the operation objects in the :class:`~.QuantumCircuit` for the output :class:`~.DAGCircuit`. This should only be set to ``False`` if the input :class:`~.QuantumCircuit` will not be used anymore as the operations in the output :class:`~.DAGCircuit` will be shared instances and modifications to operations in the :class:`~.DAGCircuit` will be reflected in the :class:`~.QuantumCircuit` (and vice versa). qubit_order (Iterable[Qubit] or None): the order that the qubits should be indexed in the output DAG. Defaults to the same order as in the circuit. clbit_order (Iterable[Clbit] or None): the order that the clbits should be indexed in the output DAG. Defaults to the same order as in the circuit. Return: DAGCircuit: the DAG representing the input circuit. Raises: ValueError: if the ``qubit_order`` or ``clbit_order`` parameters do not match the bits in the circuit. Example: .. code-block:: from qiskit import QuantumRegister, ClassicalRegister, QuantumCircuit from qiskit.dagcircuit import DAGCircuit from qiskit.converters import circuit_to_dag q = QuantumRegister(3, 'q') c = ClassicalRegister(3, 'c') circ = QuantumCircuit(q, c) circ.h(q[0]) circ.cx(q[0], q[1]) circ.measure(q[0], c[0]) circ.rz(0.5, q[1]).c_if(c, 2) dag = circuit_to_dag(circ) """ dagcircuit = DAGCircuit() dagcircuit.name = circuit.name dagcircuit.global_phase = circuit.global_phase dagcircuit.calibrations = circuit.calibrations dagcircuit.metadata = circuit.metadata if qubit_order is None: qubits = circuit.qubits elif len(qubit_order) != circuit.num_qubits or set(qubit_order) != set(circuit.qubits): raise ValueError("'qubit_order' does not contain exactly the same qubits as the circuit") else: qubits = qubit_order if clbit_order is None: clbits = circuit.clbits elif len(clbit_order) != circuit.num_clbits or set(clbit_order) != set(circuit.clbits): raise ValueError("'clbit_order' does not contain exactly the same clbits as the circuit") else: clbits = clbit_order dagcircuit.add_qubits(qubits) dagcircuit.add_clbits(clbits) for register in circuit.qregs: dagcircuit.add_qreg(register) for register in circuit.cregs: dagcircuit.add_creg(register) for instruction in circuit.data: op = instruction.operation if copy_operations: op = copy.deepcopy(op) dagcircuit.apply_operation_back(op, instruction.qubits, instruction.clbits) dagcircuit.duration = circuit.duration dagcircuit.unit = circuit.unit return dagcircuit