Sprout/sprout/numeric/dft/idft_element.hpp
2013-02-14 18:02:43 +09:00

43 lines
1.4 KiB
C++

#ifndef SPROUT_NUMERIC_DFT_IDFT_ELEMENT_HPP
#define SPROUT_NUMERIC_DFT_IDFT_ELEMENT_HPP
#include <iterator>
#include <sprout/config.hpp>
#include <sprout/math/constants.hpp>
#include <sprout/iterator/operation.hpp>
#include <sprout/numeric/dft/detail/dft_element_gen.hpp>
namespace sprout {
namespace detail {
template<typename InputIterator, typename Size>
inline SPROUT_CONSTEXPR typename std::iterator_traits<InputIterator>::value_type
idft_element_impl(
InputIterator first, InputIterator last, typename std::iterator_traits<InputIterator>::difference_type i,
Size size
)
{
typedef typename std::iterator_traits<InputIterator>::value_type value_type;
typedef typename value_type::value_type elem_type;
return sprout::detail::dft_element_gen(
first,
last,
sprout::math::two_pi<elem_type>() * i / size
)
/ static_cast<elem_type>(size)
;
}
} // namespace detail
//
// idft_element
//
template<typename InputIterator>
inline SPROUT_CONSTEXPR typename std::iterator_traits<InputIterator>::value_type
idft_element( InputIterator first, InputIterator last, typename std::iterator_traits<InputIterator>::difference_type i) {
return sprout::detail::idft_element_impl(
first, last, i,
sprout::distance(first, last)
);
}
} // namespace sprout
#endif // #ifndef SPROUT_NUMERIC_DFT_IDFT_ELEMENT_HPP