include/dai/util.h

   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 /// \file
  13 /// \brief Defines general utility functions and adds an abstraction layer for platform-dependent functionality
  14 /// \todo Improve documentation
  15
  16
  17 #ifndef __defined_libdai_util_h
  18 #define __defined_libdai_util_h
  19
  20
  21 #include <string>
  22 #include <vector>
  23 #include <set>
  24 #include <map>
  25 #include <iostream>
  26 #include <boost/foreach.hpp>
  27 #include <boost/functional/hash.hpp>
  28 #include <algorithm>
  29
  30
  31 #if defined(WINDOWS)
  32     #include <map>
  33 #elif defined(CYGWIN)
  34     #include <boost/tr1/unordered_map.hpp>
  35 #else
  36     #include <tr1/unordered_map>
  37 #endif
  38
  39
  40 /// An alias to the BOOST_FOREACH macro from the boost::foreach library
  41 #define foreach BOOST_FOREACH
  42
  43 #ifdef DAI_DEBUG
  44 /// \brief "Print variable". Prints the text of an expression, followed by its value (only if DAI_DEBUG is defined)
  45 /**
  46  *  Useful debugging macro to see what your code is doing.
  47  *  Example: \code DAI_PV(3+4) \endcode
  48  *  Output: \code 3+4= 7 \endcode
  49  */
  50 #define DAI_PV(x) do {std::cerr << #x "= " << (x) << std::endl;} while(0)
  51 /// "Debugging message": Prints a message (only if DAI_DEBUG is defined)
  52 #define DAI_DMSG(str) do {std::cerr << str << std::endl;} while(0)
  53 #else
  54 #define DAI_PV(x) do {} while(0)
  55 #define DAI_DMSG(str) do {} while(0)
  56 #endif
  57
  58 /// Produces accessor and mutator methods according to the common pattern.
  59 /** Example:
  60  *  \code DAI_ACCMUT(size_t& maxIter(), { return props.maxiter; }); \endcode
  61  *  \todo At the moment, only the mutator appears in doxygen documentation.
  62  */
  63 #define DAI_ACCMUT(x,y)                     \
  64       x y;                                  \
  65       const x const y;
  66
  67 /// Macro to give error message \a stmt if props.verbose>=\a n
  68 #define DAI_IFVERB(n, stmt) if(props.verbose>=n) { cerr << stmt; }
  69
  70
  71 /// Real number (alias for double, which could be changed to long double if necessary)
  72 typedef double Real;
  73
  74
  75 #ifdef WINDOWS
  76     /// Returns true if argument is NAN (Not A Number)
  77     bool isnan( double x );
  78
  79     /// Returns inverse hyperbolic tangent of argument
  80     double atanh( double x );
  81
  82     /// Returns log(1+x)
  83     double log1p( double x );
  84
  85     /// Define INFINITY
  86     #define INFINITY (std::numeric_limits<double>::infinity())
  87 #endif
  88
  89
  90 namespace dai {
  91
  92
  93 #ifdef WINDOWS
  94     /// hash_map is an alias for std::map.
  95     /** Since there is no TR1 unordered_map implementation available yet, we fall back on std::map.
  96      */
  97     template <typename T, typename U, typename H = boost::hash<T> >
  98         class hash_map : public std::map<T,U> {};
  99 #else
 100     /// hash_map is an alias for std::tr1::unordered_map.
 101     /** We use the (experimental) TR1 unordered_map implementation included in modern GCC distributions.
 102      */
 103     template <typename T, typename U, typename H = boost::hash<T> >
 104         class hash_map : public std::tr1::unordered_map<T,U,H> {};
 105 #endif
 106
 107
 108 /// Returns wall clock time in seconds
 109 double toc();
 110
 111
 112 /// Sets the random seed
 113 void rnd_seed( size_t seed );
 114
 115 /// Returns a real number, distributed uniformly on [0,1)
 116 double rnd_uniform();
 117
 118 /// Returns a real number from a standard-normal distribution
 119 double rnd_stdnormal();
 120
 121 /// Returns a random integer in interval [min, max]
 122 int rnd_int( int min, int max );
 123
 124 /// Returns a random integer in the half-open interval \f$[0,n)\f$
 125 inline int rnd( int n) {
 126     return rnd_int( 0, n-1 );
 127 }
 128
 129
 130 /// Writes a std::vector to a std::ostream
 131 template<class T>
 132 std::ostream& operator << (std::ostream& os, const std::vector<T> & x) {
 133     os << "(";
 134     for( typename std::vector<T>::const_iterator it = x.begin(); it != x.end(); it++ )
 135         os << (it != x.begin() ? ", " : "") << *it;
 136     os << ")";
 137     return os;
 138 }
 139
 140 /// Writes a std::set to a std::ostream
 141 template<class T>
 142 std::ostream& operator << (std::ostream& os, const std::set<T> & x) {
 143     os << "{";
 144    for( typename std::set<T>::const_iterator it = x.begin(); it != x.end(); it++ )
 145         os << (it != x.begin() ? ", " : "") << *it;
 146     os << "}";
 147     return os;
 148 }
 149
 150 /// Writes a std::map to a std::ostream
 151 template<class T1, class T2>
 152 std::ostream& operator << (std::ostream& os, const std::map<T1,T2> & x) {
 153     os << "{";
 154     for( typename std::map<T1,T2>::const_iterator it = x.begin(); it != x.end(); it++ )
 155         os << (it != x.begin() ? ", " : "") << it->first << "->" << it->second;
 156     os << "}";
 157     return os;
 158 }
 159
 160 /// Writes a std::pair to a std::ostream
 161 template<class T1, class T2>
 162 std::ostream& operator << (std::ostream& os, const std::pair<T1,T2> & x) {
 163     os << "(" << x.first << ", " << x.second << ")";
 164     return os;
 165 }
 166
 167 /// Concatenate two vectors
 168 template<class T>
 169 std::vector<T> concat( const std::vector<T>& u, const std::vector<T>& v ) {
 170     std::vector<T> w;
 171     w.reserve( u.size() + v.size() );
 172     for( size_t i = 0; i < u.size(); i++ )
 173         w.push_back( u[i] );
 174     for( size_t i = 0; i < v.size(); i++ )
 175         w.push_back( v[i] );
 176     return w;
 177 }
 178
 179 /// Split a string into tokens
 180 void tokenizeString( const std::string& s, std::vector<std::string>& outTokens, const std::string& delim="\t\n" );
 181
 182 /// Used to keep track of the progress made by iterative algorithms
 183 class Diffs : public std::vector<double> {
 184     private:
 185         size_t _maxsize;
 186         double _def;
 187         std::vector<double>::iterator _pos;
 188         std::vector<double>::iterator _maxpos;
 189     public:
 190         /// Constructor
 191         Diffs(long maxsize, double def) : std::vector<double>(), _maxsize(maxsize), _def(def) {
 192             this->reserve(_maxsize);
 193             _pos = begin();
 194             _maxpos = begin();
 195         }
 196         /// Returns maximum difference encountered
 197         double maxDiff() {
 198             if( size() < _maxsize )
 199                 return _def;
 200             else
 201                 return( *_maxpos );
 202         }
 203         /// Register new difference x
 204         void push(double x) {
 205             if( size() < _maxsize ) {
 206                 push_back(x);
 207                 _pos = end();
 208                 if( size() > 1 ) {
 209                     if( *_maxpos < back() ) {
 210                         _maxpos = end();
 211                         _maxpos--;
 212                     }
 213                 } else {
 214                     _maxpos = begin();
 215                 }
 216             } else {
 217                 if( _pos == end() )
 218                     _pos = begin();
 219                 if( _maxpos == _pos ) {
 220                     *_pos++ = x;
 221                     _maxpos = max_element(begin(),end());
 222                 } else {
 223                     if( x > *_maxpos )
 224                         _maxpos = _pos;
 225                     *_pos++ = x;
 226                 }
 227             }
 228         }
 229         /// Return maximum number of differences stored
 230         size_t maxSize() { return _maxsize; }
 231 };
 232
 233
 234 } // end of namespace dai
 235
 236
 237 #endif