Sprout/sprout/numeric/unstable_inner_product.hpp
2012-12-03 21:48:50 +09:00

89 lines
3.4 KiB
C++

#ifndef SPROUT_NUMERIC_UNSTABLE_INNNER_PRODUCT_HPP
#define SPROUT_NUMERIC_UNSTABLE_INNNER_PRODUCT_HPP
#include <iterator>
#include <sprout/config.hpp>
#include <sprout/numeric/inner_product.hpp>
#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
#include HDR_ITERATOR_SSCRISK_CEL_OR_SPROUT
namespace sprout {
//
// unstable_inner_product
//
namespace detail {
template<typename T, typename RandomAccessIterator1, typename RandomAccessIterator2, typename BinaryOperation1, typename BinaryOperation2>
inline SPROUT_CONSTEXPR T
unstable_inner_product_ra(
RandomAccessIterator1 first1, RandomAccessIterator1 last1, RandomAccessIterator2 first2,
BinaryOperation1 binary_op1, BinaryOperation2 binary_op2,
typename std::iterator_traits<RandomAccessIterator1>::difference_type pivot
)
{
return pivot == 0 ? binary_op2(*first1, *first2)
: binary_op1(
sprout::detail::unstable_inner_product_ra<T>(
first1, sprout::next(first1, pivot), first2, binary_op1, binary_op2,
pivot / 2
),
sprout::detail::unstable_inner_product_ra<T>(
sprout::next(first1, pivot), last1, sprout::next(first2, pivot), binary_op1, binary_op2,
(NS_SSCRISK_CEL_OR_SPROUT::distance(first1, last1) - pivot) / 2
)
)
;
}
template<typename RandomAccessIterator1, typename RandomAccessIterator2, typename T, typename BinaryOperation1, typename BinaryOperation2>
inline SPROUT_CONSTEXPR T
unstable_inner_product(
RandomAccessIterator1 first1, RandomAccessIterator1 last1, RandomAccessIterator2 first2, T init,
BinaryOperation1 binary_op1, BinaryOperation2 binary_op2,
std::random_access_iterator_tag*
)
{
return first1 == last1 ? init
: binary_op1(
init,
sprout::detail::unstable_inner_product_ra<T>(
first1, last1, first2, binary_op1, binary_op2,
NS_SSCRISK_CEL_OR_SPROUT::distance(first1, last1) / 2
)
)
;
}
template<typename InputIterator1, typename InputIterator2, typename T, typename BinaryOperation1, typename BinaryOperation2>
inline SPROUT_CONSTEXPR T
unstable_inner_product(
InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, T init,
BinaryOperation1 binary_op1, BinaryOperation2 binary_op2,
void*
)
{
return sprout::inner_product(first1, last1, first2, init, binary_op1, binary_op2);
}
} // namespace detail
template<typename InputIterator1, typename InputIterator2, typename T, typename BinaryOperation1, typename BinaryOperation2>
inline SPROUT_CONSTEXPR T
unstable_inner_product(
InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, T init,
BinaryOperation1 binary_op1, BinaryOperation2 binary_op2
)
{
typedef typename std::iterator_traits<InputIterator1>::iterator_category* category;
return sprout::detail::unstable_inner_product(first1, last1, first2, init, binary_op1, binary_op2, category());
}
template<typename InputIterator1, typename InputIterator2, typename T>
inline SPROUT_CONSTEXPR T
unstable_inner_product(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, T init) {
return sprout::unstable_inner_product(
first1, last1, first2, init,
sprout::plus<typename std::iterator_traits<InputIterator1>::value_type>(),
NS_SSCRISK_CEL_OR_SPROUT::multiplies<typename std::iterator_traits<InputIterator1>::value_type>()
);
}
} // namespace sprout
#endif // #ifndef SPROUT_NUMERIC_UNSTABLE_INNNER_PRODUCT_HPP