//---------------------------------------------------------------------------// // Copyright (c) 2013 Kyle Lutz // // Distributed under the Boost Software License, Version 1.0 // See accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt // // See http://boostorg.github.com/compute for more information. //---------------------------------------------------------------------------// #ifndef BOOST_COMPUTE_ALGORITHM_INNER_PRODUCT_HPP #define BOOST_COMPUTE_ALGORITHM_INNER_PRODUCT_HPP #include #include #include #include #include #include #include #include #include #include namespace boost { namespace compute { /// Returns the inner product of the elements in the range /// [\p first1, \p last1) with the elements in the range beginning /// at \p first2. /// /// Space complexity: \Omega(1)
/// Space complexity when binary operator is recognized as associative: \Omega(n) template inline T inner_product(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, T init, command_queue &queue = system::default_queue()) { BOOST_STATIC_ASSERT(is_device_iterator::value); BOOST_STATIC_ASSERT(is_device_iterator::value); typedef typename std::iterator_traits::value_type input_type; ptrdiff_t n = std::distance(first1, last1); return ::boost::compute::accumulate( ::boost::compute::make_transform_iterator( ::boost::compute::make_zip_iterator( boost::make_tuple(first1, first2) ), detail::unpack(multiplies()) ), ::boost::compute::make_transform_iterator( ::boost::compute::make_zip_iterator( boost::make_tuple(last1, first2 + n) ), detail::unpack(multiplies()) ), init, queue ); } /// \overload template inline T inner_product(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, T init, BinaryAccumulateFunction accumulate_function, BinaryTransformFunction transform_function, command_queue &queue = system::default_queue()) { BOOST_STATIC_ASSERT(is_device_iterator::value); BOOST_STATIC_ASSERT(is_device_iterator::value); typedef typename std::iterator_traits::value_type value_type; size_t count = detail::iterator_range_size(first1, last1); vector result(count, queue.get_context()); transform(first1, last1, first2, result.begin(), transform_function, queue); return ::boost::compute::accumulate(result.begin(), result.end(), init, accumulate_function, queue); } } // end compute namespace } // end boost namespace #endif // BOOST_COMPUTE_ALGORITHM_INNER_PRODUCT_HPP