polars.Expr.list.to_array#

Expr.list.to_array(width: int) → Expr[source]#

Convert a List column into an Array column with the same inner data type.

Parameters:

width: Width of the resulting Array column.

Returns:

Expr: Expression of data type Array.

Examples

>>> df = pl.DataFrame(
...     data={"a": [[1, 2], [3, 4]]},
...     schema={"a": pl.List(pl.Int8)},
... )
>>> df.with_columns(array=pl.col("a").list.to_array(2))
shape: (2, 2)
┌──────────┬──────────────┐
│ a        ┆ array        │
│ ---      ┆ ---          │
│ list[i8] ┆ array[i8, 2] │
╞══════════╪══════════════╡
│ [1, 2]   ┆ [1, 2]       │
│ [3, 4]   ┆ [3, 4]       │
└──────────┴──────────────┘