Source code for mqt.ddsim.hybridqasmsimulator

"""Backend for DDSIM Hybrid Schrodinger-Feynman Simulator."""

from __future__ import annotations

import time
from typing import TYPE_CHECKING, Any

    from qiskit import QuantumCircuit

from qiskit import QiskitError
from qiskit.providers import Options
from qiskit.result.models import ExperimentResult, ExperimentResultData
from qiskit.transpiler import Target
from qiskit.utils.multiprocessing import local_hardware_info

from .header import DDSIMHeader
from .pyddsim import HybridCircuitSimulator, HybridMode
from .qasmsimulator import QasmSimulatorBackend
from .target import DDSIMTargetBuilder

[docs] class HybridQasmSimulatorBackend(QasmSimulatorBackend): """Python interface to MQT DDSIM Hybrid Schrodinger-Feynman Simulator.""" _HSF_TARGET = Target(description="MQT DDSIM HSF Simulator Target", num_qubits=128) @staticmethod def _add_operations_to_target(target: Target) -> None: DDSIMTargetBuilder.add_0q_gates(target) DDSIMTargetBuilder.add_1q_gates(target) DDSIMTargetBuilder.add_2q_controlled_gates(target) DDSIMTargetBuilder.add_barrier(target) DDSIMTargetBuilder.add_measure(target) def __init__( self, name: str = "hybrid_qasm_simulator", description: str = "MQT DDSIM Hybrid Schrodinger-Feynman simulator", ) -> None: super().__init__(name=name, description=description) @classmethod def _default_options(cls) -> Options: return Options( shots=None, parameter_binds=None, simulator_seed=None, mode="amplitude", nthreads=local_hardware_info()["cpus"], ) @property def target(self) -> Target: return self._HSF_TARGET def _run_experiment(self, qc: QuantumCircuit, **options: Any) -> ExperimentResult: start_time = time.time() seed = options.get("seed", -1) mode = options.get("mode", "amplitude") nthreads = int(options.get("nthreads", local_hardware_info()["cpus"])) if mode == "amplitude": hybrid_mode = HybridMode.amplitude max_qubits = 30 # hard-coded 16GiB memory limit algorithm_qubits = qc.num_qubits if algorithm_qubits > max_qubits: msg = "Not enough memory available to simulate the circuit even on a single thread" raise QiskitError(msg) qubit_diff = max_qubits - algorithm_qubits nthreads = int(min(2**qubit_diff, nthreads)) elif mode == "dd": hybrid_mode = HybridMode.DD else: msg = f"Simulation mode{mode} not supported by hybrid simulator. Available modes are 'amplitude' and 'dd'." raise QiskitError(msg) sim = HybridCircuitSimulator(qc, seed=seed, mode=hybrid_mode, nthreads=nthreads) shots = options.get("shots", 1024) if self._SHOW_STATE_VECTOR and shots > 0: shots = 0 counts = sim.simulate(shots) end_time = time.time() data = ExperimentResultData( counts={hex(int(result, 2)): count for result, count in counts.items()}, statevector=None if not self._SHOW_STATE_VECTOR else sim.get_vector() if sim.get_mode() == HybridMode.DD else sim.get_final_amplitudes(), time_taken=end_time - start_time, mode=mode, nthreads=nthreads, ) return ExperimentResult( shots=shots, success=True, status="DONE", seed=seed, data=data, metadata=qc.metadata, header=DDSIMHeader(qc), )