Function _cross_merge

pandas/core/reshape/merge.py:402–452

See merge.__doc__ with how='cross'

(
    left: DataFrame,
    right: DataFrame,
    on: IndexLabel | AnyArrayLike | None = None,
    left_on: IndexLabel | AnyArrayLike | None = None,
    right_on: IndexLabel | AnyArrayLike | None = None,
    left_index: bool = False,
    right_index: bool = False,
    sort: bool = False,
    suffixes: Suffixes = ("_x", "_y"),
    indicator: str | bool = False,
    validate: str | None = None,
)

def _cross_merge(
    left: DataFrame,
    right: DataFrame,
    on: IndexLabel | AnyArrayLike | None = None,
    left_on: IndexLabel | AnyArrayLike | None = None,
    right_on: IndexLabel | AnyArrayLike | None = None,
    left_index: bool = False,
    right_index: bool = False,
    sort: bool = False,
    suffixes: Suffixes = ("_x", "_y"),
    indicator: str | bool = False,
    validate: str | None = None,
) -> DataFrame:
    """
    See merge.__doc__ with how='cross'
    """

    if (
        left_index
        or right_index
        or right_on is not None
        or left_on is not None
        or on is not None
    ):
        raise MergeError(
            "Can not pass on, right_on, left_on or set right_index=True or "
            "left_index=True"
        )

    cross_col = f"_cross_{uuid.uuid4()}"
    left = left.assign(**{cross_col: 1})
    right = right.assign(**{cross_col: 1})

    left_on = right_on = [cross_col]

    res = merge(
        left,
        right,
        how="inner",
        on=on,
        left_on=left_on,
        right_on=right_on,
        left_index=left_index,
        right_index=right_index,
        sort=sort,
        suffixes=suffixes,
        indicator=indicator,
        validate=validate,
    )
    del res[cross_col]
    return res


def _groupby_and_merge(