optuna.visualization.plot_slice(study: optuna.study.Study, params: Optional[List[str]] = None) → go.Figure[source]

Plot the parameter relationship as slice plot in a study.

Note that, If a parameter contains missing values, a trial with missing values is not plotted.


The following code snippet shows how to plot the parameter relationship as slice plot.

import optuna

def objective(trial):
    x = trial.suggest_uniform("x", -100, 100)
    y = trial.suggest_categorical("y", [-1, 0, 1])
    return x ** 2 + y

study = optuna.create_study()
study.optimize(objective, n_trials=10)

optuna.visualization.plot_slice(study, params=["x", "y"])
  • study – A Study object whose trials are plotted for their objective values.

  • params – Parameter list to visualize. The default is all parameters.


A plotly.graph_objs.Figure object.