Source code for qlauncher.routines.dwave.backends

 1"""DWave backends"""
 2
 3from abc import ABC, abstractmethod
 4
 5from qlauncher.base import Backend
 6from qlauncher.exceptions import DependencyError
 7
 8try:
 9    from dimod import Sampler
10    from dwave.samplers import SimulatedAnnealingSampler, SteepestDescentSampler, TabuSampler
11    from dwave.system import DWaveSampler, EmbeddingComposite
12except ImportError as e:
13    raise DependencyError(e, install_hint='dwave') from e
14
15

[docs]
16class BQMBackend(Backend, ABC):
17    """Base dwave backend"""
18
19    def __init__(self, name: str, parameters: list | None = None) -> None:
20        super().__init__(name, parameters)
21        self.sampler = self._get_sampler()
22
23    @abstractmethod
24    def _get_sampler(self) -> Sampler:
25        """Get a dimod sampler"""

26
27

[docs]
28class TabuBackend(BQMBackend):
29    """Tabu search simulator backend"""
30
31    def __init__(self, parameters: list | None = None) -> None:
32        super().__init__('TabuBackend', parameters)
33
34    def _get_sampler(self):
35        return TabuSampler()

36
37

[docs]
38class SimulatedAnnealingBackend(BQMBackend):
39    """Simulated annealing simulator backend"""
40
41    def __init__(self, parameters: list | None = None) -> None:
42        super().__init__('SimulatedAnnealingBackend', parameters)
43
44    def _get_sampler(self) -> Sampler:
45        return SimulatedAnnealingSampler()

46
47

[docs]
48class SteepestDescentBackend(BQMBackend):
49    """Steepest descent simulator backend"""
50
51    def __init__(self, parameters: list | None = None) -> None:
52        super().__init__('SteepestDescentBackend', parameters)
53
54    def _get_sampler(self) -> Sampler:
55        return SteepestDescentSampler()

56
57

[docs]
58class DwaveBackend(BQMBackend):
59    """Real Dwave device backend"""
60
61    def __init__(self, parameters: list | None = None) -> None:
62        super().__init__('DwaveDevice', parameters)
63
64    def _get_sampler(self) -> Sampler:
65        return EmbeddingComposite(DWaveSampler())