daft.functions.list_agg_distinct#

def list_agg_distinct(expr: Expression) -> Expression:
    """Aggregates the values in the expression into a list of distinct values (ignoring nulls).

    Returns:
        Expression: A List expression containing the distinct values from the input

    Examples:
        >>> import daft
        >>> from daft.functions import list_agg_distinct
        >>>
        >>> df = daft.from_pydict({"values": [1, 1, None, 2, 2, None]})
        >>> df.agg(list_agg_distinct(df["values"]).alias("distinct_values")).show()
        ╭─────────────────╮
        │ distinct_values │
        │ ---             │
        │ List[Int64]     │
        ╞═════════════════╡
        │ [1, 2]          │
        ╰─────────────────╯
        <BLANKLINE>
        (Showing first 1 of 1 rows)

        Note that null values are ignored by default:

        >>> df = daft.from_pydict({"values": [None, None, None]})
        >>> df.agg(list_agg_distinct(df["values"]).alias("distinct_values")).show()
        ╭─────────────────╮
        │ distinct_values │
        │ ---             │
        │ List[Null]      │
        ╞═════════════════╡
        │ []              │
        ╰─────────────────╯
        <BLANKLINE>
        (Showing first 1 of 1 rows)

    """
    return Expression._from_pyexpr(expr._expr.agg_set())