Classes
class	turi::query_eval::generic_aggregator< T, AggregateFunctionType >

class	turi::broadcast_queue< T, Serializer >

Functions
template<typename ResultType , typename ReduceFunctionType , typename AggregateFunctionType >
ResultType	turi::query_eval::reduce (std::shared_ptr< planner_node > input, ReduceFunctionType reduce_fn, AggregateFunctionType aggregate_fn, ResultType init=ResultType())

Detailed Description

Function Documentation

template<typename ResultType , typename ReduceFunctionType , typename AggregateFunctionType >

ResultType turi::query_eval::reduce	(	std::shared_ptr< planner_node >	input,
		ReduceFunctionType	reduce_fn,
		AggregateFunctionType	aggregate_fn,
		ResultType	init = `ResultType()`
	)

Performs a reduction on input in parallel, this function decides the degree of parallelism, usually depend on number of CPUs.

Parameters

input	The iterator supports parallel batch reading of items
reduce_fn	The reduction function to use. This must be of the form bool f(const array_value_type&, reduction_type&).
init	The initial value to use in the reduction

Template Parameters

ResultType	The type of the intermediate result. Must be serializable
ReduceFunctionType	The result type of each reduction.
AggregateFunctionType	The type of the reduce function

Definition at line 101 of file aggregates.hpp.