polars.Series.fill_null#

Series.fill_null(
value: Any | Expr | None = None,
strategy: FillNullStrategy | None = None,
limit: int | None = None,
) Series[source]#

Fill null values using the specified value or strategy.

Parameters:
value

Value used to fill null values.

strategy{None, ‘forward’, ‘backward’, ‘min’, ‘max’, ‘mean’, ‘zero’, ‘one’}

Strategy used to fill null values.

limit

Number of consecutive null values to fill when using the ‘forward’ or ‘backward’ strategy.

See also

fill_nan

Examples

>>> s = pl.Series("a", [1, 2, 3, None])
>>> s.fill_null(strategy="forward")
shape: (4,)
Series: 'a' [i64]
[
    1
    2
    3
    3
]
>>> s.fill_null(strategy="min")
shape: (4,)
Series: 'a' [i64]
[
    1
    2
    3
    1
]
>>> s = pl.Series("b", ["x", None, "z"])
>>> s.fill_null(pl.lit(""))
shape: (3,)
Series: 'b' [str]
[
    "x"
    ""
    "z"
]