boost/accumulators/statistics/tail_variate.hpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // tail_variate.hpp
   3 //
   4 //  Copyright 2005 Eric Niebler, Michael Gauckler. Distributed under the Boost
   5 //  Software License, Version 1.0. (See accompanying file
   6 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   7
   8 #ifndef BOOST_STAT_STATISTICS_TAIL_VARIATE_HPP_EAN_28_10_2005
   9 #define BOOST_STAT_STATISTICS_TAIL_VARIATE_HPP_EAN_28_10_2005
  10
  11 #include <boost/range.hpp>
  12 #include <boost/mpl/always.hpp>
  13 #include <boost/mpl/placeholders.hpp>
  14 #include <boost/iterator/reverse_iterator.hpp>
  15 #include <boost/iterator/permutation_iterator.hpp>
  16 #include <boost/accumulators/framework/accumulator_base.hpp>
  17 #include <boost/accumulators/framework/extractor.hpp>
  18 #include <boost/accumulators/framework/depends_on.hpp>
  19 #include <boost/accumulators/statistics_fwd.hpp>
  20 #include <boost/accumulators/statistics/tail.hpp>
  21
  22 namespace boost { namespace accumulators
  23 {
  24
  25 namespace impl
  26 {
  27     ///////////////////////////////////////////////////////////////////////////////
  28     // tail_variate_impl
  29     template<typename VariateType, typename VariateTag, typename LeftRight>
  30     struct tail_variate_impl
  31       : accumulator_base
  32     {
  33         // for boost::result_of
  34         typedef
  35             typename detail::tail_range<
  36                 typename std::vector<VariateType>::const_iterator
  37               , std::vector<std::size_t>::iterator
  38             >::type
  39         result_type;
  40
  41         template<typename Args>
  42         tail_variate_impl(Args const &args)
  43           : variates(args[tag::tail<LeftRight>::cache_size], args[parameter::keyword<VariateTag>::get() | VariateType()])
  44         {
  45         }
  46
  47         template<typename Args>
  48         void assign(Args const &args, std::size_t index)
  49         {
  50             this->variates[index] = args[parameter::keyword<VariateTag>::get()];
  51         }
  52
  53         template<typename Args>
  54         result_type result(Args const &args) const
  55         {
  56             // getting the order result causes the indices vector to be sorted.
  57             extractor<tag::tail<LeftRight> > const some_tail = {};
  58             return this->do_result(some_tail(args));
  59         }
  60
  61     private:
  62         template<typename TailRng>
  63         result_type do_result(TailRng const &rng) const
  64         {
  65             return detail::make_tail_range(
  66                 this->variates.begin()
  67               , rng.end().base().base()   // the index iterator
  68               , rng.begin().base().base() // (begin and end reversed because these are reverse iterators)
  69             );
  70         }
  71
  72         std::vector<VariateType> variates;
  73     };
  74
  75 } // namespace impl
  76
  77 ///////////////////////////////////////////////////////////////////////////////
  78 // tag::tail_variate<>
  79 //
  80 namespace tag
  81 {
  82     template<typename VariateType, typename VariateTag, typename LeftRight>
  83     struct tail_variate
  84       : depends_on<tail<LeftRight> >
  85     {
  86         /// INTERNAL ONLY
  87         ///
  88         typedef mpl::always<accumulators::impl::tail_variate_impl<VariateType, VariateTag, LeftRight> > impl;
  89     };
  90
  91     struct abstract_tail_variate
  92       : depends_on<>
  93     {
  94     };
  95
  96     template<typename LeftRight>
  97     struct tail_weights
  98       : depends_on<tail<LeftRight> >
  99     {
 100         /// INTERNAL ONLY
 101         ///
 102         typedef accumulators::impl::tail_variate_impl<mpl::_2, tag::weight, LeftRight> impl;
 103     };
 104
 105     struct abstract_tail_weights
 106       : depends_on<>
 107     {
 108     };
 109 }
 110
 111 ///////////////////////////////////////////////////////////////////////////////
 112 // extract::tail_variate
 113 // extract::tail_weights
 114 //
 115 namespace extract
 116 {
 117     extractor<tag::abstract_tail_variate> const tail_variate = {};
 118     extractor<tag::abstract_tail_weights> const tail_weights = {};
 119 }
 120
 121 using extract::tail_variate;
 122 using extract::tail_weights;
 123
 124 template<typename VariateType, typename VariateTag, typename LeftRight>
 125 struct feature_of<tag::tail_variate<VariateType, VariateTag, LeftRight> >
 126   : feature_of<tag::abstract_tail_variate>
 127 {
 128 };
 129
 130 template<typename LeftRight>
 131 struct feature_of<tag::tail_weights<LeftRight> >
 132 {
 133     typedef tag::abstract_tail_weights type;
 134 };
 135
 136 }} // namespace boost::accumulators
 137
 138 #endif