ray.data.aggregate.AggregateFnV2.combine

abstract AggregateFnV2.combine(current_accumulator: AggType, new: AggType) → AggType

Combines a new partial aggregation result with the current accumulator.

This method defines how two intermediate aggregation states are merged. For example, if aggregate_block produces partial sums s1 and s2 from two different blocks, combine(s1, s2) should return s1 + s2.

Parameters:

• current_accumulator – The current accumulated state (e.g., the result of previous combine calls or an initial value from zero_factory).

• new – A new partially aggregated value, typically the output of aggregate_block from a new block of data, or another accumulator from a parallel task.

Returns:

The updated accumulator after combining it with the new value.