Indexes of minima along the specified axis.

        Raises
        ------
        ValueError
            * If the row/column is empty

        See Also
        --------
        Series.idxmin : Return index of the minimum element.

        Notes
        -----
        This method is the DataFrame version of ``ndarray.argmin``.

        Examples
        --------
        Consider a dataset containing food consumption in Argentina.

        >>> df = pd.DataFrame({'consumption': [10.51, 103.11, 55.48],
        ...                    'co2_emissions': [37.2, 19.66, 1712]},
        ...                    index=['Pork', 'Wheat Products', 'Beef'])

        >>> df
                        consumption  co2_emissions
        Pork                  10.51         37.20
        Wheat Products       103.11         19.66
        Beef                  55.48       1712.00

        By default, it returns the index for the minimum value in each column.

        >>> df.idxmin()
        consumption                Pork
        co2_emissions    Wheat Products
        dtype: object

        To return the index for the minimum value in each row, use ``axis="columns"``.

        >>> df.idxmin(axis="columns")
        Pork                consumption
        Wheat Products    co2_emissions
        Beef                consumption
        dtype: object
        Nr|