r"""
Null Solver: Do nothing.
"""
# Copyright (c) 2024 Thinklab@SJTU
# ML4CO-Kit is licensed under Mulan PSL v2.
# You can use this software according to the terms and conditions of the Mulan PSL v2.
# You may obtain a copy of Mulan PSL v2 at:
# http://license.coscl.org.cn/MulanPSL2
# THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
# EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
# MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
# See the Mulan PSL v2 for more details.
import numpy as np
from ml4co_kit.optimizer.base import OptimizerBase
from ml4co_kit.task.base import TaskBase
from ml4co_kit.solver.base import SolverBase, SOLVER_TYPE
[docs]class NullSolver(SolverBase):
"""
Null Solver: Do nothing.
Last Update: 2026-05-26
"""
def __init__(
self,
cp_from_ref: bool = True,
optimizer: OptimizerBase = None,
):
# Super Initialization
super(NullSolver, self).__init__(
solver_type=SOLVER_TYPE.NULL, optimizer=optimizer
)
# Initialize Attributes
self.cp_from_ref = cp_from_ref
def _solve(self, task_data: TaskBase):
if self.cp_from_ref:
variable = task_data.ref_sol
if isinstance(variable, np.ndarray):
task_data.sol = variable.copy()
else:
task_data.sol = variable