Function valid_divisions

dask/dataframe/utils.py:672–713

Are the provided divisions valid? Examples -------- >>> valid_divisions([1, 2, 3]) True >>> valid_divisions([3, 2, 1]) False >>> valid_divisions([1, 1, 1]) False >>> valid_divisions([0, 1, 1]) True >>> valid_divisions((1, 2, 3)) True >>> valid_div

(divisions)

def valid_divisions(divisions):
    """Are the provided divisions valid?

    Examples
    --------
    >>> valid_divisions([1, 2, 3])
    True
    >>> valid_divisions([3, 2, 1])
    False
    >>> valid_divisions([1, 1, 1])
    False
    >>> valid_divisions([0, 1, 1])
    True
    >>> valid_divisions((1, 2, 3))
    True
    >>> valid_divisions(123)
    False
    >>> valid_divisions([0, float('nan'), 1])
    False
    """
    if not isinstance(divisions, (tuple, list)):
        return False

    # Cast tuples to lists as `pd.isnull` treats them differently
    # https://github.com/pandas-dev/pandas/issues/52283
    if isinstance(divisions, tuple):
        divisions = list(divisions)

    if pd.isnull(divisions).any():
        return False

    for i, x in enumerate(divisions[:-2]):
        if x >= divisions[i + 1]:
            return False
        if isinstance(x, Number) and math.isnan(x):
            return False

    for x in divisions[-2:]:
        if isinstance(x, Number) and math.isnan(x):
            return False

    return divisions[-2] <= divisions[-1]


class AttributeNotImplementedError(NotImplementedError, AttributeError):