polars.Expr.agg_groups#
- Expr.agg_groups() Self [source]#
Get the group indexes of the group by operation.
Should be used in aggregation context only.
Examples
>>> df = pl.DataFrame( ... { ... "group": [ ... "one", ... "one", ... "one", ... "two", ... "two", ... "two", ... ], ... "value": [94, 95, 96, 97, 97, 99], ... } ... ) >>> df.groupby("group", maintain_order=True).agg(pl.col("value").agg_groups()) shape: (2, 2) ┌───────┬───────────┐ │ group ┆ value │ │ --- ┆ --- │ │ str ┆ list[u32] │ ╞═══════╪═══════════╡ │ one ┆ [0, 1, 2] │ │ two ┆ [3, 4, 5] │ └───────┴───────────┘