ray.data.aggregate.Max#
- class ray.data.aggregate.Max(on: str | None = None, ignore_nulls: bool = True, alias_name: str | None = None)[source]#
Bases:
AggregateFnV2
Defines max aggregation.
Example
import ray from ray.data.aggregate import Max ds = ray.data.range(100) # Schema: {'id': int64} ds = ds.add_column("group_key", lambda x: x % 3) # Schema: {'id': int64, 'group_key': int64} # Finding the maximum value per group: result = ds.groupby("group_key").aggregate(Max(on="id")).take_all() # result: [{'group_key': 0, 'max(id)': ...}, # {'group_key': 1, 'max(id)': ...}, # {'group_key': 2, 'max(id)': ...}]
- Parameters:
on – The name of the column to find the maximum value from. Must be provided.
ignore_nulls – Whether to ignore null values. If
True
(default), nulls are skipped. IfFalse
, the maximum will be null if any value in the group is null (for most data types, or follow type-specific comparison rules with nulls).alias_name – Optional name for the resulting column.
Methods
Transforms the final accumulated state into the desired output.