polars.Expr.arr.contains#

Expr.arr.contains(
item: float | str | bool | int | date | datetime | time | IntoExprColumn,
) → Expr[source]#

Check if sub-arrays contain the given item.

Parameters:
item

Item that will be checked for membership

Returns:
Expr

Expression of data type Boolean.

Examples

>>> df = pl.DataFrame(
...     {"a": [["a", "b"], ["x", "y"], ["a", "c"]]},
...     schema={"a": pl.Array(pl.String, 2)},
... )
>>> df.with_columns(contains=pl.col("a").arr.contains("a"))
shape: (3, 2)
┌───────────────┬──────────┐
│ a             ┆ contains │
│ ---           ┆ ---      │
│ array[str, 2] ┆ bool     │
╞═══════════════╪══════════╡
│ ["a", "b"]    ┆ true     │
│ ["x", "y"]    ┆ false    │
│ ["a", "c"]    ┆ true     │
└───────────────┴──────────┘