(
        self,
        attrs: Tuple[str, ...] = (
            "number",
            "value",
            "datetime_start",
            "datetime_complete",
            "duration",
            "params",
            "user_attrs",
            "system_attrs",
            "state",
        ),
        multi_index: bool = False,
    )
return _dataframe._trials_dataframe(self, attrs, multi_index)
Export trials as a pandas DataFrame_.

        The DataFrame_ provides various features to analyze studies. It is also useful to draw a
        histogram of objective values and to export trials as a CSV file.
        If there are no trials, an empty DataFrame_ is returned.

        Example:

            .. testcode::

                import optuna
                import pandas


                def objective(trial):
                    x = trial.suggest_float("x", -1, 1)
                    return x ** 2


                study = optuna.create_study()
                study.optimize(objective, n_trials=3)

                # Create a dataframe from the study.
                df = study.trials_dataframe()
                assert isinstance(df, pandas.DataFrame)
                assert df.shape[0] == 3  # n_trials.

        Args:
            attrs:
                Specifies field names of :class:`~optuna.trial.FrozenTrial` to include them to a
                DataFrame of trials.
            multi_index:
                Specifies whether the returned DataFrame_ employs MultiIndex_ or not. Columns that
                are hierarchical by nature such as ``(params, x)`` will be flattened to
                ``params_x`` when set to :obj:`False`.

        Returns:
            A pandas DataFrame_ of trials in the :class:`~optuna.study.Study`.

        .. _DataFrame: http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.html
        .. _MultiIndex: https://pandas.pydata.org/pandas-docs/stable/advanced.html

        Note:
            If ``value`` is in ``attrs`` during multi-objective optimization, it is implicitly
            replaced with ``values``.
Export trials as a pandas DataFrame_.
Export trials as a pandas DataFrame_ .
def trials_dataframe(
        self,
        attrs: Tuple[str, ...] = (
            "number",
            "value",
            "datetime_start",
            "datetime_complete",
            "duration",
            "params",
            "user_attrs",
            "system_attrs",
            "state",
        ),
        multi_index: bool = False,
    ) -> "pd.DataFrame":
        """Export trials as a pandas DataFrame_.

        The DataFrame_ provides various features to analyze studies. It is also useful to draw a
        histogram of objective values and to export trials as a CSV file.
        If there are no trials, an empty DataFrame_ is returned.

        Example:

            .. testcode::

                import optuna
                import pandas


                def objective(trial):
                    x = trial.suggest_float("x", -1, 1)
                    return x ** 2


                study = optuna.create_study()
                study.optimize(objective, n_trials=3)

                # Create a dataframe from the study.
                df = study.trials_dataframe()
                assert isinstance(df, pandas.DataFrame)
                assert df.shape[0] == 3  # n_trials.

        Args:
            attrs:
                Specifies field names of :class:`~optuna.trial.FrozenTrial` to include them to a
                DataFrame of trials.
            multi_index:
                Specifies whether the returned DataFrame_ employs MultiIndex_ or not. Columns that
                are hierarchical by nature such as ``(params, x)`` will be flattened to
                ``params_x`` when set to :obj:`False`.

        Returns:
            A pandas DataFrame_ of trials in the :class:`~optuna.study.Study`.

        .. _DataFrame: http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.html
        .. _MultiIndex: https://pandas.pydata.org/pandas-docs/stable/advanced.html

        Note:
            If ``value`` is in ``attrs`` during multi-objective optimization, it is implicitly
            replaced with ``values``.
        """
        return _dataframe._trials_dataframe(self, attrs, multi_index)
def trials_dataframe ( self , attrs : Tuple [ str , ... ] = ( "number" , "value" , "datetime_start" , "datetime_complete" , "duration" , "params" , "user_attrs" , "system_attrs" , "state" , ) , multi_index : bool = False , ) -> "pd.DataFrame" : return _dataframe . _trials_dataframe ( self , attrs , multi_index )