ceph/src/boost/boost/math/tools/stats.hpp

   1 //  (C) Copyright John Maddock 2005-2006.
   2 //  Use, modification and distribution are subject to the
   3 //  Boost Software License, Version 1.0. (See accompanying file
   4 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef BOOST_MATH_TOOLS_STATS_INCLUDED
   7 #define BOOST_MATH_TOOLS_STATS_INCLUDED
   8
   9 #ifdef _MSC_VER
  10 #pragma once
  11 #endif
  12
  13 #include <boost/config/no_tr1/cmath.hpp>
  14 #include <boost/cstdint.hpp>
  15 #include <boost/math/tools/precision.hpp>
  16
  17 namespace boost{ namespace math{ namespace tools{
  18
  19 template <class T>
  20 class stats
  21 {
  22 public:
  23    stats()
  24       : m_min(tools::max_value<T>()),
  25         m_max(-tools::max_value<T>()),
  26         m_total(0),
  27         m_squared_total(0),
  28         m_count(0)
  29    {}
  30    void add(const T& val)
  31    {
  32       if(val < m_min)
  33          m_min = val;
  34       if(val > m_max)
  35          m_max = val;
  36       m_total += val;
  37       ++m_count;
  38       m_squared_total += val*val;
  39    }
  40    T min BOOST_PREVENT_MACRO_SUBSTITUTION()const{ return m_min; }
  41    T max BOOST_PREVENT_MACRO_SUBSTITUTION()const{ return m_max; }
  42    T total()const{ return m_total; }
  43    T mean()const{ return m_total / static_cast<T>(m_count); }
  44    boost::uintmax_t count()const{ return m_count; }
  45    T variance()const
  46    {
  47       BOOST_MATH_STD_USING
  48
  49       T t = m_squared_total - m_total * m_total / m_count;
  50       t /= m_count;
  51       return t;
  52    }
  53    T variance1()const
  54    {
  55       BOOST_MATH_STD_USING
  56
  57       T t = m_squared_total - m_total * m_total / m_count;
  58       t /= (m_count-1);
  59       return t;
  60    }
  61    T rms()const
  62    {
  63       BOOST_MATH_STD_USING
  64
  65       return sqrt(m_squared_total / static_cast<T>(m_count));
  66    }
  67    stats& operator+=(const stats& s)
  68    {
  69       if(s.m_min < m_min)
  70          m_min = s.m_min;
  71       if(s.m_max > m_max)
  72          m_max = s.m_max;
  73       m_total += s.m_total;
  74       m_squared_total += s.m_squared_total;
  75       m_count += s.m_count;
  76       return *this;
  77    }
  78 private:
  79    T m_min, m_max, m_total, m_squared_total;
  80    boost::uintmax_t m_count;
  81 };
  82
  83 } // namespace tools
  84 } // namespace math
  85 } // namespace boost
  86
  87 #endif
  88