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Bayesian Optimization

Bayesian Optimization

HEBO (Heteroscedastic and Evolutionary Bayesian Optimisation)

Class or Function Names HEBOSampler Installation # Install the dependencies. pip install optunahub hebo # NOTE: Below is optional, but pymoo must be installed after NumPy for faster HEBOSampler, # we run the following command to make sure that the compiled version is installed. pip install --upgrade pymoo APIs HEBOSampler(search_space: dict[str, BaseDistribution] | None = None, *, seed: int | None = None, constant_liar: bool = False, independent_sampler: BaseSampler | None = None) search_space: By specifying search_space, the sampling speed at each iteration becomes slightly quicker, but this argument is not necessary to run this sampler.

PFNs4BO sampler

Class or Function Names PFNs4BOSampler Installation pip install -r https://hub.optuna.org/samplers/pfns4bo/requirements.txt Example from __future__ import annotations import os import optuna import optunahub module = optunahub.load_module("samplers/pfns4bo") PFNs4BOSampler = module.PFNs4BOSampler def objective(trial: optuna.Trial) -> float: x = trial.suggest_float("x", -10, 10) return (x - 2) ** 2 if __name__ == "__main__": study = optuna.create_study( sampler=PFNs4BOSampler(), ) study.optimize(objective, n_trials=100) print(study.best_params) print(study.best_value) See example.py for a full example. You need GPU to run this example. The following figures are experimental results of the comparison between PFNs4BO and the random search.

PLMBO (Preference Learning Multi-Objective Bayesian Optimization)

Class or Function Names PLMBOSampler Installation pip install -r https://hub.optuna.org/samplers/plmbo/requirements.txt Example from __future__ import annotations import matplotlib.pyplot as plt import optuna import optunahub from optuna.distributions import FloatDistribution import numpy as np PLMBOSampler = optunahub.load_module( # type: ignore "samplers/plmbo", ).PLMBOSampler if __name__ == "__main__": f_sigma = 0.01 def obj_func1(x): return np.sin(x[0]) + x[1] def obj_func2(x): return -np.sin(x[0]) - x[1] + 0.1 def obs_obj_func(x): return np.array( [ obj_func1(x) + np.random.normal(0, f_sigma), obj_func2(x) + np.

SMAC3

APIs A sampler that uses SMAC3 v2.2.0 verified by unittests that can be run by the following: $ pip install pytest optunahub smac $ python -m pytest package/samplers/smac_sampler/tests/ Please check the API reference for more details: https://automl.github.io/SMAC3/main/5_api.html SMACSampler(search_space: dict[str, BaseDistribution], n_trials: int = 100, seed: int | None = None, *, surrogate_model_type: str = "rf", acq_func_type: str = "ei_log", init_design_type: str = "sobol", surrogate_model_rf_num_trees: int = 10, surrogate_model_rf_ratio_features: float = 1.