Source code for ax.benchmark.benchmark_problem

# Copyright (c) Meta Platforms, Inc. and affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.


import abc
from typing import Any, Dict, List, Optional, Type

from ax.core.metric import Metric

from ax.core.objective import MultiObjective, Objective
from ax.core.optimization_config import (
    MultiObjectiveOptimizationConfig,
    ObjectiveThreshold,
    OptimizationConfig,
)
from ax.core.parameter import ParameterType, RangeParameter
from ax.core.runner import Runner
from ax.core.search_space import SearchSpace
from ax.core.types import ComparisonOp
from ax.metrics.botorch_test_problem import BotorchTestProblemMetric
from ax.runners.botorch_test_problem import BotorchTestProblemRunner
from ax.utils.common.base import Base
from botorch.test_functions.base import BaseTestProblem
from botorch.test_functions.multi_objective import MultiObjectiveTestProblem
from botorch.test_functions.synthetic import SyntheticTestFunction

# NOTE: Do not add `from __future__ import annotatations` to this file. Adding
# `annotations` postpones evaluation of types and will break FBLearner's usage of
# `BenchmarkProblem` as return type annotation, used for serialization and rendering
# in the UI.


def _get_name(
    test_problem: BaseTestProblem, infer_noise: bool, dim: Optional[int] = None
) -> str:
    """
    Get a string name describing the problem, in a format such as
    "hartmann_fixed_noise_6d" or "jenatton" (where the latter would
    not have fixed noise and have the default dimensionality).
    """
    base_name = f"{test_problem.__class__.__name__}"
    fixed_noise = "" if infer_noise else "_fixed_noise"
    dim_str = "" if dim is None else f"_{dim}d"
    return f"{base_name}{fixed_noise}{dim_str}"


[docs]class BenchmarkProblemBase(abc.ABC): """ Specifies the interface any benchmark problem must adhere to. Subclasses include BenchmarkProblem, SurrogateBenchmarkProblem, and MOOSurrogateBenchmarkProblem. """ name: str search_space: SearchSpace optimization_config: OptimizationConfig num_trials: int infer_noise: bool tracking_metrics: List[Metric] @abc.abstractproperty def runner(self) -> Runner: pass # pragma: no cover
[docs]class BenchmarkProblem(Base, BenchmarkProblemBase): """Benchmark problem, represented in terms of Ax search space, optimization config, and runner. """ def __init__( self, name: str, search_space: SearchSpace, optimization_config: OptimizationConfig, runner: Runner, num_trials: int, infer_noise: bool, tracking_metrics: Optional[List[Metric]] = None, ) -> None: self.name = name self.search_space = search_space self.optimization_config = optimization_config self._runner = runner self.num_trials = num_trials self.infer_noise = infer_noise self.tracking_metrics: List[Metric] = ( [] if tracking_metrics is None else tracking_metrics ) @property def runner(self) -> Runner: return self._runner
[docs] @classmethod def from_botorch( cls, test_problem_class: Type[BaseTestProblem], test_problem_kwargs: Dict[str, Any], num_trials: int, infer_noise: bool = True, ) -> "BenchmarkProblem": """ Create a BenchmarkProblem from a BoTorch BaseTestProblem using specialized Metrics and Runners. The test problem's result will be computed on the Runner and retrieved by the Metric. Args: test_problem_class: The BoTorch test problem class which will be used to define the `search_space`, `optimization_config`, and `runner`. test_problem_kwargs: Keyword arguments used to instantiate the `test_problem_class`. num_trials: Simply the `num_trials` of the `BenchmarkProblem` created. infer_noise: Whether noise will be inferred. This is separate from whether synthetic noise is added to the problem, which is controlled by the `noise_std` of the test problem. """ # pyre-fixme [45]: Invalid class instantiation test_problem = test_problem_class(**test_problem_kwargs) search_space = SearchSpace( parameters=[ RangeParameter( name=f"x{i}", parameter_type=ParameterType.FLOAT, lower=test_problem._bounds[i][0], upper=test_problem._bounds[i][1], ) for i in range(test_problem.dim) ] ) dim = test_problem_kwargs.get("dim", None) name = _get_name(test_problem, infer_noise, dim) optimization_config = OptimizationConfig( objective=Objective( metric=BotorchTestProblemMetric( name=name, noise_sd=None if infer_noise else (test_problem.noise_std or 0), ), minimize=True, ) ) return cls( name=name, search_space=search_space, optimization_config=optimization_config, runner=BotorchTestProblemRunner( test_problem_class=test_problem_class, test_problem_kwargs=test_problem_kwargs, ), num_trials=num_trials, infer_noise=infer_noise, )
[docs]class SingleObjectiveBenchmarkProblem(BenchmarkProblem): """The most basic BenchmarkProblem, with a single objective and a known optimal value. """ def __init__( self, optimal_value: float, *, name: str, search_space: SearchSpace, optimization_config: OptimizationConfig, runner: Runner, num_trials: int, infer_noise: bool, tracking_metrics: Optional[List[Metric]] = None, ) -> None: super().__init__( name=name, search_space=search_space, optimization_config=optimization_config, runner=runner, num_trials=num_trials, infer_noise=infer_noise, tracking_metrics=tracking_metrics, ) self.optimal_value = optimal_value
[docs] @classmethod def from_botorch_synthetic( cls, test_problem_class: Type[SyntheticTestFunction], test_problem_kwargs: Dict[str, Any], num_trials: int, infer_noise: bool = True, ) -> "SingleObjectiveBenchmarkProblem": """Create a BenchmarkProblem from a BoTorch BaseTestProblem using specialized Metrics and Runners. The test problem's result will be computed on the Runner and retrieved by the Metric. """ # pyre-fixme [45]: Invalid class instantiation test_problem = test_problem_class(**test_problem_kwargs) problem = BenchmarkProblem.from_botorch( test_problem_class=test_problem_class, test_problem_kwargs=test_problem_kwargs, num_trials=num_trials, infer_noise=infer_noise, ) dim = test_problem_kwargs.get("dim", None) name = _get_name(test_problem, infer_noise, dim) return cls( name=name, search_space=problem.search_space, optimization_config=problem.optimization_config, runner=problem.runner, num_trials=num_trials, infer_noise=infer_noise, optimal_value=test_problem.optimal_value, )
[docs]class MultiObjectiveBenchmarkProblem(BenchmarkProblem): """A BenchmarkProblem support multiple objectives. Rather than knowing each objective's optimal value we track a known maximum hypervolume computed from a given reference point. """ def __init__( self, maximum_hypervolume: float, reference_point: List[float], *, name: str, search_space: SearchSpace, optimization_config: OptimizationConfig, runner: Runner, num_trials: int, infer_noise: bool, tracking_metrics: Optional[List[Metric]] = None, ) -> None: self.maximum_hypervolume = maximum_hypervolume self.reference_point = reference_point super().__init__( name=name, search_space=search_space, optimization_config=optimization_config, runner=runner, num_trials=num_trials, infer_noise=infer_noise, tracking_metrics=tracking_metrics, )
[docs] @classmethod def from_botorch_multi_objective( cls, test_problem_class: Type[MultiObjectiveTestProblem], test_problem_kwargs: Dict[str, Any], num_trials: int, infer_noise: bool = True, ) -> "MultiObjectiveBenchmarkProblem": """Create a BenchmarkProblem from a BoTorch BaseTestProblem using specialized Metrics and Runners. The test problem's result will be computed on the Runner once per trial and each Metric will retrieve its own result by index. """ # pyre-fixme [45]: Invalid class instantiation test_problem = test_problem_class(**test_problem_kwargs) problem = BenchmarkProblem.from_botorch( test_problem_class=test_problem_class, test_problem_kwargs=test_problem_kwargs, num_trials=num_trials, infer_noise=infer_noise, ) dim = test_problem_kwargs.get("dim", None) name = _get_name(test_problem, infer_noise, dim) metrics = [ BotorchTestProblemMetric( name=f"{name}_{i}", noise_sd=None if infer_noise else (test_problem.noise_std or 0), index=i, ) for i in range(test_problem.num_objectives) ] optimization_config = MultiObjectiveOptimizationConfig( objective=MultiObjective( objectives=[ Objective( metric=metric, minimize=True, ) for metric in metrics ] ), objective_thresholds=[ ObjectiveThreshold( metric=metrics[i], bound=test_problem.ref_point[i].item(), relative=False, op=ComparisonOp.LEQ, ) for i in range(test_problem.num_objectives) ], ) return cls( name=name, search_space=problem.search_space, optimization_config=optimization_config, runner=problem.runner, num_trials=num_trials, infer_noise=infer_noise, maximum_hypervolume=test_problem.max_hv, reference_point=test_problem._ref_point, )