polars.LazyFrame.explode

LazyFrame.explode(columns: str | list[str] | polars.internals.expr.expr.Expr | list[polars.internals.expr.expr.Expr]) → LDF

Explode lists to long format.

Examples

>>> df = pl.DataFrame(
...     {
...         "letters": ["a", "a", "b", "c"],
...         "numbers": [[1], [2, 3], [4, 5], [6, 7, 8]],
...     }
... ).lazy()
>>> df.explode("numbers").collect()
shape: (8, 2)
┌─────────┬─────────┐
│ letters ┆ numbers │
│ ---     ┆ ---     │
│ str     ┆ i64     │
╞═════════╪═════════╡
│ a       ┆ 1       │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┤
│ a       ┆ 2       │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┤
│ a       ┆ 3       │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┤
│ b       ┆ 4       │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┤
│ b       ┆ 5       │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┤
│ c       ┆ 6       │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┤
│ c       ┆ 7       │
├╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┤
│ c       ┆ 8       │
└─────────┴─────────┘