polars.Series.list.shift#

Series.list.shift(n: int | IntoExprColumn = 1) → Series[source]#

Shift list values by the given number of indices.

Parameters:

n: Number of indices to shift forward. If a negative value is passed, values are shifted in the opposite direction instead.

Notes

This method is similar to the LAG operation in SQL when the value for n is positive. With a negative value for n, it is similar to LEAD.

Examples

By default, list values are shifted forward by one index.

>>> s = pl.Series([[1, 2, 3], [4, 5]])
>>> s.list.shift()
shape: (2,)
Series: '' [list[i64]]
[
        [null, 1, 2]
        [null, 4]
]

Pass a negative value to shift in the opposite direction instead.

>>> s.list.shift(-2)
shape: (2,)
Series: '' [list[i64]]
[
        [3, null, null]
        [null, null]
]