polars.DataFrame.shift#

DataFrame.shift(periods: int) → Self[source]#

Shift values by the given period.

Parameters:

periods: Number of places to shift (may be negative).

See also

shift_and_fill

Examples

>>> df = pl.DataFrame(
...     {
...         "foo": [1, 2, 3],
...         "bar": [6, 7, 8],
...         "ham": ["a", "b", "c"],
...     }
... )
>>> df.shift(periods=1)
shape: (3, 3)
┌──────┬──────┬──────┐
│ foo  ┆ bar  ┆ ham  │
│ ---  ┆ ---  ┆ ---  │
│ i64  ┆ i64  ┆ str  │
╞══════╪══════╪══════╡
│ null ┆ null ┆ null │
│ 1    ┆ 6    ┆ a    │
│ 2    ┆ 7    ┆ b    │
└──────┴──────┴──────┘
>>> df.shift(periods=-1)
shape: (3, 3)
┌──────┬──────┬──────┐
│ foo  ┆ bar  ┆ ham  │
│ ---  ┆ ---  ┆ ---  │
│ i64  ┆ i64  ┆ str  │
╞══════╪══════╪══════╡
│ 2    ┆ 7    ┆ b    │
│ 3    ┆ 8    ┆ c    │
│ null ┆ null ┆ null │
└──────┴──────┴──────┘