extl/intelligence/ann/standardized_converter.h

   1 /* ///////////////////////////////////////////////////////////////////////
   2  * File:                standardized_converter.h
   3  *
   4  * Created:             09.04.05
   5  * Updated:             09.04.05
   6  *
   7  * Brief:               The standardized_converter class
   8  *
   9  * [<Home>]
  10  * Copyright (c) 2008-2020, Waruqi All rights reserved.
  11  * //////////////////////////////////////////////////////////////////// */
  12
  13 #ifndef EXTL_INTELLIGENCE_ANN_STANDARDIZED_CONVERTER_H
  14 #define EXTL_INTELLIGENCE_ANN_STANDARDIZED_CONVERTER_H
  15
  16 /*!\file standardized_converter.h
  17  * \brief standardized_converter class
  18  */
  19
  20 /* ///////////////////////////////////////////////////////////////////////
  21  * Compatibility
  22  */
  23 #if !defined(EXTL_INTELLIGENCE_ANN_NETWORK_SUPPORT)
  24 #       error standardized_converter.h is not supported by the current compiler.
  25 #endif
  26
  27 /* ///////////////////////////////////////////////////////////////////////
  28  * Includes
  29  */
  30 #include "prefix.h"
  31
  32 /* ///////////////////////////////////////////////////////////////////////
  33  * ::extl::intelligence namespace
  34  */
  35 EXTL_INTELLIGENCE_BEGIN_WHOLE_NAMESPACE
  36
  37
  38 /*!brief standardized_converter
  39  *
  40  * \param InN the input demension
  41  * \param OutN the output demension
  42  *
  43  * \ingroup extl_group_intelligence
  44  */
  45 template<       e_size_t InN
  46                 ,       e_size_t OutN
  47                 >
  48 class standardized_converter
  49 {
  50         /// \name Types
  51         /// @{
  52         public:
  53                 typedef standardized_converter                                                                                          class_type;
  54                 typedef e_size_t                                                                                                                        size_type;
  55                 typedef e_bool_t                                                                                                                        bool_type;
  56                 typedef e_size_t                                                                                                                        index_type;
  57                 typedef e_float_t                                                                                                                       float_type;
  58                 typedef typename_type_k vvector_selector<float_type>::vvector_type                      vector_type;
  59                 typedef vector_type                                                                                                                     floats_type;
  60                 typedef typename_type_k sample_selector<InN, OutN>::float_sample_type           sample_type;
  61                 typedef typename_type_k buffer_selector<sample_type>::large_buffer_type         samples_type;
  62         /// @}
  63
  64         /// \name Members
  65         /// @{
  66         private:
  67                 vector_type                                                                                                                                     m_avgs;
  68                 vector_type                                                                                                                                     m_sds;
  69         /// @}
  70
  71         /// \name Accessors
  72         /// @{
  73         public:
  74                 vector_type&                    avgs()                  {       return m_avgs;  }
  75                 vector_type const&              avgs() const    {       return m_avgs;  }
  76
  77                 vector_type&                    sds()                   {       return m_sds;   }
  78                 vector_type const&              sds() const             {       return m_sds;   }
  79         /// @}
  80
  81         /// \name Methods
  82         /// @{
  83         public:
  84                 /// standardize samples: (x - avg) / sd
  85                 /// \note only convert the input data of samples
  86                 void    convert_input(samples_type& sps)
  87                 {
  88                         size_type input_n = sample_type::en_input_size;
  89                         // (x - avg) / sd
  90                         index_type i = 0, j = 0;
  91                         size_type sps_n = sps.size();
  92                         EXTL_ASSERT(sps_n > 1);
  93
  94                         // averages
  95                         vector_type avgs(0.0, input_n);
  96                         for (i = 0; i < sps_n; ++i)
  97                                 avgs += sps[i].input();
  98                         avgs /= sps_n;
  99
 100                         // standard deviation
 101                         vector_type sds(0.0, input_n);
 102                         for (i = 0; i < sps_n; ++i)
 103                                 sds += (sps[i].input() - avgs).dot_pow2();
 104                         sds /= sps_n - 1;
 105
 106                         for (j = 0; j < input_n; ++j)
 107                         {
 108                                 sds[j] = xtl_sqrt(sds[j]);
 109                                 if (xtl_abs(sds[j]) < 1e-10) sds[j] = 1e-10;
 110                         }
 111
 112                         // standardize
 113                         for (i = 0; i < sps_n; ++i)
 114                                 sps[i].input() = (sps[i].input() - avgs).dot_div(sds);
 115
 116                         // updates averages and standard deviation
 117                         m_avgs = avgs;
 118                         m_sds = sds;
 119                 }
 120
 121                 /// standardize sample: (x - avg) / sd
 122                 /// \note only convert the input data of sample
 123                 void    convert_input(sample_type& sp)
 124                 {
 125                         sp.input() = (sp.input() - m_avgs).dot_div(m_sds);
 126                 }
 127                 /// restore standardized sample: x * sd + avg
 128                 /// \note only convert the input data of sample
 129                 void    restore_input(sample_type& sp)
 130                 {
 131                         sp.input() = sp.input().dot_mul(m_sds) + m_avgs;
 132                 }
 133         /// @}
 134 };
 135
 136
 137 /* ///////////////////////////////////////////////////////////////////////
 138  * ::extl::intelligence namespace
 139  */
 140 EXTL_INTELLIGENCE_END_WHOLE_NAMESPACE
 141
 142 /* //////////////////////////////////////////////////////////////////// */
 143 #endif  /* EXTL_INTELLIGENCE_ANN_STANDARDIZED_CONVERTER_H */
 144 /* //////////////////////////////////////////////////////////////////// */