C++ High Performance

Performance evaluation

Let's see how std::nth_element() and std::partial_sort()measure up against std::sort(). We've measured with 10,000,000 elements in total and a partial range of 1,000,000 elements:

Operation	Code, where r is the range operated on	Speed up:
Sort	sort(r.begin(), r.end());	1.00x
Find median	auto middle = r.begin() + r.size() / 2;nth_element(r.begin(), middle, r.end());	12.41x
Find the values as if fully ordered From left_idx to right_idx List unordered	auto left_it = r.begin() + left_idx;auto right_it = r.begin() + right_idx;nth_element(r.begin(), left_it,r.end());nth_element(left_it, right_it, r.end());	8.70x
Find the values as if fully ordered From left_idx to right_idx List ordered	auto left_it = r.begin() ...