polars.Expr.str.slice#

Expr.str.slice(offset: int, length: int | None = None) → Expr[source]#

Create subslices of the string values of a Utf8 Series.

Parameters:

offset: Start index. Negative indexing is supported.
length: Length of the slice. If set to None (default), the slice is taken to the end of the string.

Returns:

Expr: Expression of data type Utf8.

Examples

>>> df = pl.DataFrame({"s": ["pear", None, "papaya", "dragonfruit"]})
>>> df.with_columns(
...     pl.col("s").str.slice(-3).alias("s_sliced"),
... )
shape: (4, 2)
┌─────────────┬──────────┐
│ s           ┆ s_sliced │
│ ---         ┆ ---      │
│ str         ┆ str      │
╞═════════════╪══════════╡
│ pear        ┆ ear      │
│ null        ┆ null     │
│ papaya      ┆ aya      │
│ dragonfruit ┆ uit      │
└─────────────┴──────────┘

Using the optional length parameter

>>> df.with_columns(
...     pl.col("s").str.slice(4, length=3).alias("s_sliced"),
... )
shape: (4, 2)
┌─────────────┬──────────┐
│ s           ┆ s_sliced │
│ ---         ┆ ---      │
│ str         ┆ str      │
╞═════════════╪══════════╡
│ pear        ┆          │
│ null        ┆ null     │
│ papaya      ┆ ya       │
│ dragonfruit ┆ onf      │
└─────────────┴──────────┘