libstdc++-v3/testsuite/util/statistic/result_recorder.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2018 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the terms
   7 // of the GNU General Public License as published by the Free Software
   8 // Foundation; either version 3, or (at your option) any later
   9 // version.
  10
  11 // This library is distributed in the hope that it will be useful, but
  12 // WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 // General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License
  17 // along with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20
  21 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
  22
  23 // Permission to use, copy, modify, sell, and distribute this software
  24 // is hereby granted without fee, provided that the above copyright
  25 // notice appears in all copies, and that both that copyright notice
  26 // and this permission notice appear in supporting documentation. None
  27 // of the above authors, nor IBM Haifa Research Laboratories, make any
  28 // representation about the suitability of this software for any
  29 // purpose. It is provided "as is" without express or implied
  30 // warranty.
  31
  32 /**
  33  * @file result_recorder.hpp
  34  * Contains a class for recording results
  35  */
  36
  37 #ifndef PB_DS_RES_RECORDER_HPP
  38 #define PB_DS_RES_RECORDER_HPP
  39
  40 #include <statistic/sample_mean.hpp>
  41 #include <statistic/sample_variance.hpp>
  42 #include <statistic/sample_mean_confidence_checker.hpp>
  43
  44 namespace __gnu_pbds
  45 {
  46   namespace test
  47   {
  48     namespace detail
  49     {
  50       /*
  51        * Records results until the probability that the sample mean is 10% away
  52        * from the true mean is ~ 0.05.
  53        */
  54       template<typename Value_Type>
  55       class result_recorder
  56       {
  57       public:
  58         typedef Value_Type value_type;
  59
  60         result_recorder()
  61         : m_sample_mean(value_type()), m_sample_var(value_type())
  62         { }
  63
  64         bool
  65         add_result(value_type res);
  66
  67         inline value_type
  68         get_sample_mean() const
  69         { return m_sample_mean; }
  70
  71       private:
  72         typedef std::list<value_type> list_type;
  73
  74         list_type m_l;
  75         value_type m_sample_mean;
  76         value_type m_sample_var;
  77       };
  78
  79
  80       template<typename Value_Type>
  81       bool
  82       result_recorder<Value_Type>::
  83       add_result(value_type res)
  84       {
  85         m_l.push_back(res);
  86         m_sample_mean = sample_mean(m_l.begin(), m_l.end());
  87         m_sample_var = sample_variance(m_l.begin(), m_l.end(), m_sample_mean);
  88
  89         size_t dist = std::distance(m_l.begin(), m_l.end());
  90         return sample_mean_confidence_checker(m_sample_mean, m_sample_var,
  91                                               dist, 0.1);
  92       }
  93     } // namespace detail
  94   } // namespace test
  95 } // namespace __gnu_pbds
  96
  97 #endif
  98