optuna.study.create_study
- optuna.study.create_study(*, storage=None, sampler=None, pruner=None, study_name=None, direction=None, load_if_exists=False, directions=None)[source]
Create a new
Study.Example
import optuna def objective(trial): x = trial.suggest_float("x", 0, 10) return x**2 study = optuna.create_study() study.optimize(objective, n_trials=3)
- Parameters:
storage (str | storages.BaseStorage | None) –
Database URL. If this argument is set to None,
InMemoryStorageis used, and theStudywill not be persistent.Note
When a database URL is passed, Optuna internally uses SQLAlchemy to handle the database. Please refer to SQLAlchemy’s document for further details. If you want to specify non-default options to SQLAlchemy Engine, you can instantiate
RDBStoragewith your desired options and pass it to thestorageargument instead of a URL.sampler ('samplers.BaseSampler' | None) – A sampler object that implements background algorithm for value suggestion. If
Noneis specified,TPESampleris used during single-objective optimization andNSGAIISamplerduring multi-objective optimization. See alsosamplers.pruner (pruners.BasePruner | None) – A pruner object that decides early stopping of unpromising trials. If
Noneis specified,MedianPruneris used as the default. See alsopruners.study_name (str | None) – Study’s name. If this argument is set to None, a unique name is generated automatically.
direction (str | StudyDirection | None) –
Direction of optimization. Set
minimizefor minimization andmaximizefor maximization. You can also pass the correspondingStudyDirectionobject.directionanddirectionsmust not be specified at the same time.Note
If none of direction and directions are specified, the direction of the study is set to “minimize”.
load_if_exists (bool) – Flag to control the behavior to handle a conflict of study names. In the case where a study named
study_namealready exists in thestorage, aDuplicatedStudyErroris raised ifload_if_existsis set toFalse. Otherwise, the creation of the study is skipped, and the existing one is returned.directions (Sequence[str | StudyDirection] | None) – A sequence of directions during multi-objective optimization.
directionanddirectionsmust not be specified at the same time.
- Returns:
A
Studyobject.- Return type:
See also
optuna.create_study()is an alias ofoptuna.study.create_study().See also
The Saving/Resuming Study with RDB Backend tutorial provides concrete examples to save and resume optimization using RDB.