Source code for pytket.extensions.qiskit.tket_pass

# Copyright 2019-2024 Cambridge Quantum Computing
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from typing import Optional
from qiskit.dagcircuit import DAGCircuit  # type: ignore
from qiskit.providers import BackendV1  # type: ignore
from qiskit.transpiler.basepasses import TransformationPass, BasePass as qBasePass  # type: ignore
from qiskit.converters import circuit_to_dag, dag_to_circuit  # type: ignore
from qiskit.providers.aer.aerprovider import AerProvider  # type: ignore # type: ignore
from qiskit_ibm_provider import IBMProvider  # type: ignore


from pytket.passes import BasePass
from pytket.extensions.qiskit import (
    IBMQBackend,
    AerBackend,
    AerStateBackend,
    AerUnitaryBackend,
)
from .qiskit_convert import qiskit_to_tk, tk_to_qiskit


[docs]class TketPass(TransformationPass): """The tket compiler to be plugged in to the Qiskit compilation sequence"""
[docs] def __init__(self, tket_pass: BasePass): """Wraps a pytket compiler pass as a :py:class:`qiskit.transpiler.TransformationPass`. A :py:class:`qiskit.dagcircuit.DAGCircuit` is converted to a pytket :py:class:`Circuit`. `tket_pass` will be run and the result is converted back. :param tket_pass: The pytket compiler pass to run :type tket_pass: BasePass """ qBasePass.__init__(self) self._pass = tket_pass
[docs] def run(self, dag: DAGCircuit) -> DAGCircuit: """Run a preconfigured optimisation pass on the circuit and route for the given backend. :param dag: The circuit to optimise and route :return: The modified circuit """ qc = dag_to_circuit(dag) old_parameters = qc.parameters circ = qiskit_to_tk(qc) self._pass.apply(circ) qc = tk_to_qiskit(circ) new_param_lookup = {p._symbol_expr: p for p in qc.parameters} subs_map = {new_param_lookup[p._symbol_expr]: p for p in old_parameters} qc.assign_parameters(subs_map, inplace=True) newdag = circuit_to_dag(qc) newdag.name = dag.name return newdag
[docs]class TketAutoPass(TketPass): """The tket compiler to be plugged in to the Qiskit compilation sequence""" _aer_backend_map = { "aer_simulator": AerBackend, "aer_simulator_statevector": AerStateBackend, "aer_simulator_unitary": AerUnitaryBackend, }
[docs] def __init__( self, backend: BackendV1, optimisation_level: int = 2, token: Optional[str] = None, ): """Identifies a Qiskit backend and provides the corresponding default compilation pass from pytket as a :py:class:`qiskit.transpiler.TransformationPass`. :param backend: The Qiskit backend to target. Accepts Aer or IBMQ backends. :param optimisation_level: The level of optimisation to perform during compilation. Level 0 just solves the device constraints without optimising. Level 1 additionally performs some light optimisations. Level 2 adds more computationally intensive optimisations. Defaults to 2. :type optimisation_level: int, optional :param token: Authentication token to use the `QiskitRuntimeService`. :type token: Optional[str] """ if isinstance(backend._provider, AerProvider): tk_backend = self._aer_backend_map[backend.name]() elif isinstance(backend._provider, IBMProvider): tk_backend = IBMQBackend(backend.name, token=token) else: raise NotImplementedError("This backend provider is not supported.") super().__init__(tk_backend.default_compilation_pass(optimisation_level))