Abstract
This package automatically selects an appropriate sampler for the provided search space based on the developers’ recommendation. The following article provides detailed information about AutoSampler.

Class or Function Names
- AutoSampler
This sampler currently accepts only seed and constraints_func.
constraints_func enables users to handle constraints along with the objective function.
These arguments follow the same convention as the other samplers, so please take a look at the reference.
Installation
This sampler requires optional dependencies of Optuna.
$ pip install optunahub cmaes torch scipy
Note that since we may update the implementation of AutoSampler, it is highly encouraged to use the latest version of Optuna.
Example
import optuna
import optunahub
def objective(trial):
x = trial.suggest_float("x", -5, 5)
y = trial.suggest_float("y", -5, 5)
return x**2 + y**2
module = optunahub.load_module(package="samplers/auto_sampler")
study = optuna.create_study(sampler=module.AutoSampler())
study.optimize(objective, n_trials=300)
Test
To execute the tests for AutoSampler, please run the following commands. The test file is provided in the package.
pip install pytest
pytest package/samplers/auto_sampler/tests/
- Package
- samplers/auto_sampler
- Author
- Optuna Team
- License
- MIT License
- Verified Optuna version
- 4.5.0
- Last update
- 2025-08-29