Template Function thrust::inner_product(InputIterator1, InputIterator1, InputIterator2, OutputType, BinaryFunction1, BinaryFunction2)

Function Documentation

template<typename InputIterator1, typename InputIterator2, typename OutputType, typename BinaryFunction1, typename BinaryFunction2>
OutputType thrust::inner_product(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, OutputType init, BinaryFunction1 binary_op1, BinaryFunction2 binary_op2)

inner_product calculates an inner product of the ranges [first1, last1) and [first2, first2 + (last1 - first1)).

This version of inner_product is identical to the first, except that is uses two user-supplied function objects instead of operator+ and operator*.

Specifically, this version of inner_product computes the sum binary_op1( init, binary_op2(*first1, *first2) ), ...

Unlike the C++ Standard Template Library function std::inner_product, this version offers no guarantee on order of execution.

#include <thrust/inner_product.h>
...
float vec1[3] = {1.0f, 2.0f, 5.0f};
float vec2[3] = {4.0f, 1.0f, 5.0f};

float init = 0.0f;
thrust::plus<float>       binary_op1;
thrust::multiplies<float> binary_op2;

float result = thrust::inner_product(vec1, vec1 + 3, vec2, init, binary_op1, binary_op2);

// result == 31.0f
Return

The inner product of sequences [first1, last1) and [first2, last2).

Parameters

  • first1: The beginning of the first sequence.

  • last1: The end of the first sequence.

  • first2: The beginning of the second sequence.

  • init: Initial value of the result.

  • binary_op1: Generalized addition operation.

  • binary_op2: Generalized multiplication operation.

Template Parameters

  • InputIterator1: is a model of Input Iterator, and InputIterator1's value_type is convertible to BinaryFunction2's first_argument_type.

  • InputIterator2: is a model of Input Iterator. and InputIterator2's value_type is convertible to BinaryFunction2's second_argument_type.

  • OutputType: is a model of Assignable, and OutputType is convertible to BinaryFunction1's first_argument_type.

  • BinaryFunction1: is a model of Binary Function, and BinaryFunction1's return_type is convertible to OutputType.

  • BinaryFunction2: is a model of Binary Function, and BinaryFunction2's return_type is convertible to BinaryFunction1's second_argument_type.

See

http://www.sgi.com/tech/stl/inner_product.html