Source code for discrete_optimization.tsp.tsp_solvers

#  Copyright (c) 2022 AIRBUS and its affiliates.
#  This source code is licensed under the MIT license found in the
#  LICENSE file in the root directory of this source tree.

from typing import Any, Dict, List, Sequence, Tuple, Type

from discrete_optimization.generic_tools.cp_tools import CPSolverName
from discrete_optimization.generic_tools.do_problem import Problem
from discrete_optimization.generic_tools.result_storage.result_storage import (
    ResultStorage,
)
from discrete_optimization.tsp.solver.solver_lp_iterative import (
    LP_TSP_Iterative,
    MILPSolver,
)
from discrete_optimization.tsp.solver.solver_ortools import TSP_ORtools
from discrete_optimization.tsp.solver.tsp_cp_solver import TSP_CP_Solver, TSP_CPModel
from discrete_optimization.tsp.solver.tsp_solver import SolverTSP
from discrete_optimization.tsp.tsp_model import (
    TSPModel,
    TSPModel2D,
    TSPModelDistanceMatrix,
)

solvers: Dict[str, List[Tuple[Type[SolverTSP], Dict[str, Any]]]] = {
    "lp": [
        (
            LP_TSP_Iterative,
            {"method": MILPSolver.CBC, "nb_iteration_max": 20, "plot": False},
        )
    ],
    "ortools": [(TSP_ORtools, {})],
    "cp": [
        (
            TSP_CP_Solver,
            {
                "model_type": TSP_CPModel.INT_VERSION,
                "cp_solver_name": CPSolverName.CHUFFED,
            },
        )
    ],
}

solvers_map = {}
for key in solvers:
    for solver, param in solvers[key]:
        solvers_map[solver] = (key, param)

solvers_compatibility: Dict[Type[SolverTSP], List[Type[Problem]]] = {}
for x in solvers:
    for y in solvers[x]:
        solvers_compatibility[y[0]] = [TSPModel2D, TSPModelDistanceMatrix]


[docs] def look_for_solver(domain: TSPModel) -> List[Type[SolverTSP]]: class_domain = domain.__class__ return look_for_solver_class(class_domain)
[docs] def look_for_solver_class(class_domain: Type["TSPModel"]) -> List[Type[SolverTSP]]: available = [] for solver in solvers_compatibility: if class_domain in solvers_compatibility[solver]: available += [solver] return available
[docs] def solve(method: Type[SolverTSP], problem: TSPModel, **kwargs: Any) -> ResultStorage: solver = method(problem=problem, **kwargs) try: solver.init_model(**kwargs) except AttributeError: pass return solver.solve(**kwargs)
[docs] def return_solver( method: Type[SolverTSP], problem: TSPModel, **kwargs: Any ) -> SolverTSP: solver = method(problem, **kwargs) try: solver.init_model(**kwargs) except: pass return solver