adjacent_difference.hpp

Go to the documentation of this file.

// SPDX-License-Identifier: BSL-1.0
#ifndef TETL_NUMERIC_ADJACENT_DIFFERENCE_HPP
#define TETL_NUMERIC_ADJACENT_DIFFERENCE_HPP
 
#include <etl/_functional/minus.hpp>
#include <etl/_iterator/iterator_traits.hpp>
#include <etl/_utility/move.hpp>
 
namespace etl {

template <typename InputIt, typename OutputIt, typename BinaryOperation>
constexpr auto adjacent_difference(InputIt first, InputIt last, OutputIt destination, BinaryOperation op) -> OutputIt
{
    if (first == last) {
        return destination;
    }
 
    auto acc     = *first;
    *destination = acc;
 
    while (++first != last) {
        auto val       = *first;
        *++destination = op(val, etl::move(acc));
        acc            = etl::move(val);
    }
 
    return ++destination;
}

template <typename InputIt, typename OutputIt>
constexpr auto adjacent_difference(InputIt first, InputIt last, OutputIt destination) -> OutputIt
{
    using value_t = typename etl::iterator_traits<InputIt>::value_type;
    return etl::adjacent_difference(first, last, destination, etl::minus<value_t>());
}
 
} // namespace etl
 
#endif // TETL_NUMERIC_ADJACENT_DIFFERENCE_HPP