...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::accumulators::impl::covariance_impl — Covariance Estimator.
// In header: <boost/accumulators/statistics_fwd.hpp> template<typename Sample, typename VariateType, typename VariateTag> struct covariance_impl : public accumulator_base { // construct/copy/destruct template<typename Args> covariance_impl(Args const &); // public member functions template<typename Args> void operator()(Args const &); result_type result(dont_care) const; };