Method sort

python/ray/data/dataset.py:3747–3814

Sort the dataset by the specified key column or key function. The `key` parameter must be specified (i.e., it cannot be `None`). .. note:: If provided, the `boundaries` parameter can only be used to partition the first sort key. Examples:

(
        self,
        key: Union[str, List[str]],
        descending: Union[bool, List[bool]] = False,
        boundaries: List[Union[int, float]] = None,
    )

    @AllToAllAPI
    @PublicAPI(api_group=SSR_API_GROUP)
    def sort(
        self,
        key: Union[str, List[str]],
        descending: Union[bool, List[bool]] = False,
        boundaries: List[Union[int, float]] = None,
    ) -> "Dataset":
        """Sort the dataset by the specified key column or key function.
        The `key` parameter must be specified (i.e., it cannot be `None`).

        .. note::
            If provided, the `boundaries` parameter can only be used to partition
            the first sort key.

        Examples:
            >>> import ray
            >>> ds = ray.data.range(15)
            >>> ds = ds.sort("id", descending=False, boundaries=[5, 10])
            >>> for df in ray.get(ds.to_pandas_refs()):
            ...     print(df)
               id
            0   0
            1   1
            2   2
            3   3
            4   4
               id
            0   5
            1   6
            2   7
            3   8
            4   9
               id
            0  10
            1  11
            2  12
            3  13
            4  14

        Time complexity: O(dataset size * log(dataset size / parallelism))

        Args:
            key: The column or a list of columns to sort by.
            descending: Whether to sort in descending order. Must be a boolean or a list
                of booleans matching the number of the columns.
            boundaries: The list of values based on which to repartition the dataset.
                For example, if the input boundary is [10,20], rows with values less
                than 10 will be divided into the first block, rows with values greater
                than or equal to 10 and less than 20 will be divided into the
                second block, and rows with values greater than or equal to 20
                will be divided into the third block. If not provided, the
                boundaries will be sampled from the input blocks. This feature
                only supports numeric columns right now.

        Returns:
            A new, sorted :class:`Dataset`.

        Raises:
            ``ValueError``: if the sort key is None.