Source code for qlauncher.routines.dwave.backends

 1"""DWave backends"""
 2
 3from abc import abstractmethod, ABC
 4from dimod import Sampler
 5from qlauncher.base import Backend
 6
 7
 8from qlauncher.exceptions import DependencyError
 9
10try:
11    from dimod import Sampler
12    from dwave.system import DWaveSampler, EmbeddingComposite
13    from dwave.samplers import SimulatedAnnealingSampler, TabuSampler, SteepestDescentSampler
14except ImportError as e:
15    raise DependencyError(e, install_hint='dwave') from e
16
17

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

28
29

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

38
39

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

48
49

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

58
59

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