typename Container::value_type maximum_by(Compare comp,
const Container& xs)
{
internal::check_compare_for_container<Compare, Container>();
assert(is_not_empty(xs));
return *std::max_element(std::begin(xs), std::end(xs), comp);
}
Result median(const Container& xs)
{
assert(is_not_empty(xs));
if (size_of_cont(xs) == 1)
return static_cast<Result>(xs.front());
// std::nth_element (instead of sorting)
// would be faster for random-access containers
// but not work at all on other containers like std::list.
auto xsSorted = sort(xs);
if (size_of_cont(xsSorted) % 2 == 1)
{
auto it = std::begin(xsSorted);
internal::advance_iterator(it, size_of_cont(xsSorted) / 2);
return static_cast<Result>(*it);
}
else
{
auto it1 = std::begin(xsSorted);
internal::advance_iterator(it1, size_of_cont(xsSorted) / 2 - 1);
auto it2 = it1;
++it2;
return static_cast<Result>(*it1 + *it2) / static_cast<Result>(2);
}
}
typename std::size_t maximum_idx_by(Compare comp,
const Container& xs)
{
internal::check_compare_for_container<Compare, Container>();
assert(is_not_empty(xs));
return static_cast<std::size_t>(std::distance(std::begin(xs),
std::max_element(std::begin(xs), std::end(xs), comp)));
}
//TODO at other end
bool try_steal(JOB& job)
{
lock_type lock(m_mutex);
if (is_not_empty())
{
job = m_jobs.back();
m_jobs.pop_back();
return true;
}
return false;
}
T elem_at_idx_or_wrap(signed int idx, const Container& xs)
{
assert(is_not_empty(xs));
const signed int cont_size = static_cast<signed int>(size_of_cont(xs));
if (idx < 0)
idx = cont_size - (std::abs(idx) % cont_size);
else
idx = idx % cont_size;
auto it = std::begin(xs);
internal::advance_iterator(it, static_cast<std::size_t>(idx));
return *it;
}
T elem_at_idx_or_replicate(signed int idx, const Container& xs)
{
assert(is_not_empty(xs));
if (idx < 0)
{
return xs.front();
}
if (idx >= static_cast<signed int>(size_of_cont(xs)))
{
return xs.back();
}
auto it = std::begin(xs);
internal::advance_iterator(it, static_cast<std::size_t>(idx));
return *it;
}
Container extrapolate_wrap(std::size_t count_begin, std::size_t count_end,
const Container& xs)
{
assert(is_not_empty(xs));
Container ys;
const auto xs_size = size_of_cont(xs);
internal::prepare_container(ys, xs_size + count_begin + count_end);
auto it = internal::get_back_inserter<Container>(ys);
const signed int idx_end = static_cast<signed int>(xs_size + count_end);
const signed int idx_start = -static_cast<signed int>(count_begin);
for (signed int idx = idx_start; idx < idx_end; ++idx)
{
*it = elem_at_idx_or_wrap(idx, xs);
}
return ys;
}
Result median(const Container& xs)
{
assert(is_not_empty(xs));
if (size_of_cont(xs) == 1)
return static_cast<Result>(xs.front());
auto xsSorted = sort(xs);
if (size_of_cont(xsSorted) % 2 == 1)
{
auto it = std::begin(xsSorted);
internal::advance_iterator(it, size_of_cont(xsSorted) / 2);
return static_cast<Result>(*it);
}
else
{
auto it1 = std::begin(xsSorted);
internal::advance_iterator(it1, size_of_cont(xsSorted) / 2 - 1);
auto it2 = it1;
++it2;
return static_cast<Result>(*it1 + *it2) / static_cast<Result>(2);
}
}
