| /////////////////////////////////////////////////////////////////////////////// |
| // weighted_sum.hpp |
| // |
| // Copyright 2006 Eric Niebler, Olivier Gygi. Distributed under the Boost |
| // Software License, Version 1.0. (See accompanying file |
| // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| |
| #ifndef BOOST_ACCUMULATORS_STATISTICS_WEIGHTED_SUM_HPP_EAN_28_10_2005 |
| #define BOOST_ACCUMULATORS_STATISTICS_WEIGHTED_SUM_HPP_EAN_28_10_2005 |
| |
| #include <boost/mpl/placeholders.hpp> |
| #include <boost/accumulators/framework/accumulator_base.hpp> |
| #include <boost/accumulators/framework/extractor.hpp> |
| #include <boost/accumulators/numeric/functional.hpp> |
| #include <boost/accumulators/framework/parameters/sample.hpp> |
| #include <boost/accumulators/framework/parameters/weight.hpp> |
| #include <boost/accumulators/framework/accumulators/external_accumulator.hpp> |
| #include <boost/accumulators/framework/depends_on.hpp> |
| #include <boost/accumulators/statistics_fwd.hpp> |
| |
| namespace boost { namespace accumulators |
| { |
| |
| namespace impl |
| { |
| /////////////////////////////////////////////////////////////////////////////// |
| // weighted_sum_impl |
| template<typename Sample, typename Weight, typename Tag> |
| struct weighted_sum_impl |
| : accumulator_base |
| { |
| typedef typename numeric::functional::multiplies<Sample, Weight>::result_type weighted_sample; |
| |
| // for boost::result_of |
| typedef weighted_sample result_type; |
| |
| template<typename Args> |
| weighted_sum_impl(Args const &args) |
| : weighted_sum_( |
| args[parameter::keyword<Tag>::get() | Sample()] |
| * numeric::one<Weight>::value |
| ) |
| { |
| } |
| |
| template<typename Args> |
| void operator ()(Args const &args) |
| { |
| // what about overflow? |
| this->weighted_sum_ += args[parameter::keyword<Tag>::get()] * args[weight]; |
| } |
| |
| result_type result(dont_care) const |
| { |
| return this->weighted_sum_; |
| } |
| |
| private: |
| |
| weighted_sample weighted_sum_; |
| }; |
| |
| } // namespace impl |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // tag::weighted_sum |
| // |
| namespace tag |
| { |
| struct weighted_sum |
| : depends_on<> |
| { |
| /// INTERNAL ONLY |
| /// |
| typedef accumulators::impl::weighted_sum_impl<mpl::_1, mpl::_2, tag::sample> impl; |
| }; |
| |
| template<typename VariateType, typename VariateTag> |
| struct weighted_sum_of_variates |
| : depends_on<> |
| { |
| /// INTERNAL ONLY |
| /// |
| typedef accumulators::impl::weighted_sum_impl<VariateType, mpl::_2, VariateTag> impl; |
| }; |
| |
| struct abstract_weighted_sum_of_variates |
| : depends_on<> |
| { |
| }; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // extract::weighted_sum |
| // |
| namespace extract |
| { |
| extractor<tag::weighted_sum> const weighted_sum = {}; |
| extractor<tag::abstract_weighted_sum_of_variates> const weighted_sum_of_variates = {}; |
| |
| BOOST_ACCUMULATORS_IGNORE_GLOBAL(weighted_sum) |
| BOOST_ACCUMULATORS_IGNORE_GLOBAL(weighted_sum_of_variates) |
| } |
| |
| using extract::weighted_sum; |
| using extract::weighted_sum_of_variates; |
| |
| template<typename VariateType, typename VariateTag> |
| struct feature_of<tag::weighted_sum_of_variates<VariateType, VariateTag> > |
| : feature_of<tag::abstract_weighted_sum_of_variates> |
| { |
| }; |
| |
| }} // namespace boost::accumulators |
| |
| #endif |