from optuna.logging import get_logger
from optuna.study import Study
from optuna.study import StudyDirection
from optuna.trial import TrialState
from optuna.visualization._plotly_imports import _imports
if _imports.is_successful():
from optuna.visualization._plotly_imports import go
_logger = get_logger(__name__)
[docs]def plot_optimization_history(study: Study) -> "go.Figure":
"""Plot optimization history of all trials in a study.
Example:
The following code snippet shows how to plot optimization history.
.. testcode::
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_optimization_history(study)
.. raw:: html
<iframe src="../../_static/plot_optimization_history.html"
width="100%" height="500px" frameborder="0">
</iframe>
Args:
study:
A :class:`~optuna.study.Study` object whose trials are plotted for their objective
values.
Returns:
A :class:`plotly.graph_objs.Figure` object.
"""
_imports.check()
return _get_optimization_history_plot(study)
def _get_optimization_history_plot(study: Study) -> "go.Figure":
layout = go.Layout(
title="Optimization History Plot",
xaxis={"title": "#Trials"},
yaxis={"title": "Objective Value"},
)
trials = [t for t in study.trials if t.state == TrialState.COMPLETE]
if len(trials) == 0:
_logger.warning("Study instance does not contain trials.")
return go.Figure(data=[], layout=layout)
best_values = [float("inf")] if study.direction == StudyDirection.MINIMIZE else [-float("inf")]
comp = min if study.direction == StudyDirection.MINIMIZE else max
for trial in trials:
trial_value = trial.value
assert trial_value is not None # For mypy
best_values.append(comp(best_values[-1], trial_value))
best_values.pop(0)
traces = [
go.Scatter(
x=[t.number for t in trials],
y=[t.value for t in trials],
mode="markers",
name="Objective Value",
),
go.Scatter(x=[t.number for t in trials], y=best_values, name="Best Value"),
]
figure = go.Figure(data=traces, layout=layout)
return figure