daft.functions.date_trunc#

def date_trunc(interval: str, expr: Expression, relative_to: Expression | None = None) -> Expression:
    """Truncates the datetime column to the specified interval.

    Args:
        interval: The interval to truncate to. Must be a string representing a valid interval in "{integer} {unit}" format, e.g. "1 day". Valid time units are: 'microsecond', 'millisecond', 'second', 'minute', 'hour', 'day', 'week'.
        expr: The datetime expression to truncate.
        relative_to (optional): Timestamp to truncate relative to. If not provided, truncates to the start of the Unix epoch: 1970-01-01 00:00:00.

    Returns:
        Expression: a DateTime expression truncated to the specified interval

    Examples:
        >>> import datetime
        >>> import daft
        >>> from daft.functions import date_trunc
        >>>
        >>> df = daft.from_pydict(
        ...     {
        ...         "datetime": [
        ...             datetime.datetime(2021, 1, 1, 0, 1, 1),
        ...             datetime.datetime(2021, 1, 1, 0, 1, 59),
        ...             datetime.datetime(2021, 1, 1, 0, 2, 0),
        ...         ],
        ...     }
        ... )
        >>> df.with_column("truncated", date_trunc("1 minute", df["datetime"])).collect()
        ╭─────────────────────┬─────────────────────╮
        │ datetime            ┆ truncated           │
        │ ---                 ┆ ---                 │
        │ Timestamp[us]       ┆ Timestamp[us]       │
        ╞═════════════════════╪═════════════════════╡
        │ 2021-01-01 00:01:01 ┆ 2021-01-01 00:01:00 │
        ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
        │ 2021-01-01 00:01:59 ┆ 2021-01-01 00:01:00 │
        ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
        │ 2021-01-01 00:02:00 ┆ 2021-01-01 00:02:00 │
        ╰─────────────────────┴─────────────────────╯
        <BLANKLINE>
        (Showing first 3 of 3 rows)

    """
    return Expression._call_builtin_scalar_fn("truncate", expr, relative_to, interval=interval)