polars.Expr.str.concat#

Expr.str.concat(delimiter: str = '-', *, ignore_nulls: bool = True) Expr[source]#

Vertically concat the values in the Series to a single string value.

Parameters:
delimiter

The delimiter to insert between consecutive string values.

ignore_nulls

Ignore null values (default).

If set to False, null values will be propagated. if the column contains any null values, the output is None.

Returns:
Expr

Expression of data type Utf8.

Examples

>>> df = pl.DataFrame({"foo": [1, None, 2]})
>>> df.select(pl.col("foo").str.concat("-"))
shape: (1, 1)
┌─────┐
│ foo │
│ --- │
│ str │
╞═════╡
│ 1-2 │
└─────┘
>>> df = pl.DataFrame({"foo": [1, None, 2]})
>>> df.select(pl.col("foo").str.concat("-", ignore_nulls=False))
shape: (1, 1)
┌──────┐
│ foo  │
│ ---  │
│ str  │
╞══════╡
│ null │
└──────┘