src/util.cpp

   1 /*  Copyright (C) 2006-2008  Joris Mooij  [joris dot mooij at tuebingen dot mpg dot de]
   2     Radboud University Nijmegen, The Netherlands /
   3     Max Planck Institute for Biological Cybernetics, Germany
   4
   5     This file is part of libDAI.
   6
   7     libDAI is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     libDAI is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License
  18     along with libDAI; if not, write to the Free Software
  19     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  20 */
  21
  22
  23 #include <dai/util.h>
  24 #include <boost/random/linear_congruential.hpp>
  25 #include <boost/random/uniform_real.hpp>
  26 #include <boost/random/normal_distribution.hpp>
  27 #include <boost/random/variate_generator.hpp>
  28
  29 #ifdef WINDOWS
  30     #include <windows.h>
  31     #include <boost/math/special_functions/atanh.hpp>  // for atanh
  32     #include <boost/math/special_functions/log1p.hpp>  // for log1p
  33     #include <float.h>  // for _isnan
  34 #else
  35     // Assume POSIX compliant system. We need the following for querying the CPU time for this process
  36     #include <sys/times.h>
  37     #include <sys/param.h>
  38 #endif
  39
  40
  41 #ifdef WINDOWS
  42 bool isnan( double x ) {
  43     return _isnan( x );
  44 }
  45 double atanh( double x ) {
  46     return boost::math::atanh( x );
  47 }
  48 double log1p( double x ) {
  49     return boost::math::log1p( x );
  50 }
  51 #endif
  52
  53
  54 namespace dai {
  55
  56
  57 // Returns user+system time in seconds
  58 double toc() {
  59 #ifdef WINDOWS
  60     SYSTEMTIME  tbuf;
  61     GetSystemTime(&tbuf);
  62     return( (double)(tbuf.wSecond + (double)tbuf.wMilliseconds / 1000.0) );
  63 #else
  64     tms tbuf;
  65     times(&tbuf);
  66     return( (double)(tbuf.tms_utime + tbuf.tms_stime) / HZ );
  67 #endif
  68 }
  69
  70 // This is a typedef for a random number generator.
  71 // Try boost::mt19937 or boost::ecuyer1988 instead of boost::minstd_rand
  72 typedef boost::minstd_rand _rnd_gen_type;
  73
  74 _rnd_gen_type _rnd_gen(42U);
  75
  76 // Define a uniform random number distribution which produces
  77 // values between 0 and 1 (0 inclusive, 1 exclusive).
  78 boost::uniform_real<> _uni_dist(0,1);
  79 boost::variate_generator<_rnd_gen_type&, boost::uniform_real<> > _uni_rnd(_rnd_gen, _uni_dist);
  80
  81 // Define a normal distribution with mean 0 and standard deviation 1.
  82 boost::normal_distribution<> _normal_dist;
  83 boost::variate_generator<_rnd_gen_type&, boost::normal_distribution<> > _normal_rnd(_rnd_gen, _normal_dist);
  84
  85
  86 void rnd_seed( size_t seed ) {
  87     _rnd_gen.seed(seed);
  88 }
  89
  90 double rnd_uniform() {
  91     return _uni_rnd();
  92 }
  93
  94 double rnd_stdnormal() {
  95     return _normal_rnd();
  96 }
  97
  98 int rnd_int( int min, int max ) {
  99     return (int)floor(_uni_rnd() * (max + 1 - min) + min);
 100 }
 101
 102
 103 } // end of namespace dai