src/util.cpp

   1 /*  This file is part of libDAI - http://www.libdai.org/
   2  *
   3  *  libDAI is licensed under the terms of the GNU General Public License version
   4  *  2, or (at your option) any later version. libDAI is distributed without any
   5  *  warranty. See the file COPYING for more details.
   6  *
   7  *  Copyright (C) 2006-2009  Joris Mooij  [joris dot mooij at libdai dot org]
   8  *  Copyright (C) 2006-2007  Radboud University Nijmegen, The Netherlands
   9  */
  10
  11
  12 #include <dai/util.h>
  13 #include <boost/random/linear_congruential.hpp>
  14 #include <boost/random/uniform_real.hpp>
  15 #include <boost/random/normal_distribution.hpp>
  16 #include <boost/random/variate_generator.hpp>
  17
  18 #ifdef WINDOWS
  19     #include <windows.h>
  20     #include <boost/math/special_functions/atanh.hpp>  // for atanh
  21     #include <boost/math/special_functions/log1p.hpp>  // for log1p
  22     #include <float.h>  // for _isnan
  23 #else
  24     // Assume POSIX compliant system. We need the following for querying the system time
  25     #include <sys/time.h>
  26 #endif
  27
  28
  29 #ifdef CYGWIN
  30 bool isnan( double x ) {
  31     return __isnand( x );  // isnan() is a macro in Cygwin (as required by C99)
  32 }
  33 #endif
  34
  35 #ifdef WINDOWS
  36 bool isnan( double x ) {
  37     return _isnan( x );
  38 }
  39 double atanh( double x ) {
  40     return boost::math::atanh( x );
  41 }
  42 double log1p( double x ) {
  43     return boost::math::log1p( x );
  44 }
  45 #endif
  46
  47
  48 namespace dai {
  49
  50
  51 Real max( const std::vector<Real> &v ) {
  52     if( v.size() == 0 )
  53         return INFINITY;
  54     else
  55         return *std::max_element( v.begin(), v.end() );
  56 }
  57
  58 // Returns user+system time in seconds
  59 double toc() {
  60 #ifdef WINDOWS
  61     SYSTEMTIME tbuf;
  62     GetSystemTime(&tbuf);
  63     return( (double)(tbuf.wSecond + (double)tbuf.wMilliseconds / 1000.0) );
  64 #else
  65     struct timeval tv;
  66     struct timezone tz;
  67     gettimeofday( &tv, &tz );
  68     return( (double)(tv.tv_sec + (double)tv.tv_usec / 1000000.0) );
  69 #endif
  70 }
  71
  72 /// Type of global random number generator
  73 typedef boost::minstd_rand _rnd_gen_type;  // Try boost::mt19937 or boost::ecuyer1988 instead of boost::minstd_rand
  74
  75 /// Global random number generator
  76 _rnd_gen_type _rnd_gen(42U);
  77
  78 /// Uniform distribution with values between 0 and 1 (0 inclusive, 1 exclusive).
  79 boost::uniform_real<Real> _uni_dist(0,1);
  80
  81 /// Global uniform random random number
  82 boost::variate_generator<_rnd_gen_type&, boost::uniform_real<Real> > _uni_rnd(_rnd_gen, _uni_dist);
  83
  84 /// Normal distribution with mean 0 and standard deviation 1.
  85 boost::normal_distribution<Real> _normal_dist;
  86
  87 /// Global random number generator with standard normal distribution
  88 boost::variate_generator<_rnd_gen_type&, boost::normal_distribution<Real> > _normal_rnd(_rnd_gen, _normal_dist);
  89
  90
  91 void rnd_seed( size_t seed ) {
  92     _rnd_gen.seed(seed);
  93 }
  94
  95 Real rnd_uniform() {
  96     return _uni_rnd();
  97 }
  98
  99 Real rnd_stdnormal() {
 100     return _normal_rnd();
 101 }
 102
 103 int rnd_int( int min, int max ) {
 104     return (int)floor(_uni_rnd() * (max + 1 - min) + min);
 105 }
 106
 107 void tokenizeString(const std::string& s, std::vector<std::string>& outTokens, const std::string& delim) {
 108     size_t start = 0;
 109     while (start < s.size()) {
 110         size_t end = s.find_first_of(delim, start);
 111         if (end > s.size())
 112             end = s.size();
 113         outTokens.push_back(s.substr(start, end - start));
 114         start = end + 1;
 115     }
 116 }
 117
 118 } // end of namespace dai