daft.functions.hamming_distance_str#

def hamming_distance_str(left: Expression, right: Expression) -> Expression:
    """Compute the character-level Hamming distance between two strings.

    The Hamming distance is the number of positions at which the corresponding
    characters are different.

    Args:
        left: The left string expression to compare.
        right: The right string expression to compare against.

    Returns:
        The Hamming distance for each pair of strings. Returns null when either input
        is null or the two strings have different lengths.

    Examples:
        >>> import daft
        >>> from daft.functions import hamming_distance_str
        >>> df = daft.from_pydict({"x": ["ronald", "ronald", "ronald"], "y": ["ronald", "renuld", "ronaldo"]})
        >>> df = df.with_column("distance", hamming_distance_str(df["x"], df["y"]))
        >>> df.collect()
        ╭────────┬─────────┬──────────╮
        │ x      ┆ y       ┆ distance │
        │ ---    ┆ ---     ┆ ---      │
        │ String ┆ String  ┆ Int64    │
        ╞════════╪═════════╪══════════╡
        │ ronald ┆ ronald  ┆ 0        │
        ├╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌┤
        │ ronald ┆ renuld  ┆ 2        │
        ├╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌┤
        │ ronald ┆ ronaldo ┆ None     │
        ╰────────┴─────────┴──────────╯
        <BLANKLINE>
        (Showing first 3 of 3 rows)
    """
    return Expression._call_builtin_scalar_fn("hamming_distance_str", left, right)