| Geant4 Cross Reference |
1 // -*- C++ -*-
2 //
3 // -----------------------------------------------------------------------
4 // HEP Random
5 // --- HepRandom ---
6 // class header file
7 // -----------------------------------------------------------------------
8 // This file is part of Geant4 (simulation toolkit for HEP).
9 //
10 // It's a singleton instantiated by default within the HEP Random module.
11 // It uses an instantiated HepJamesRandom engine as default algorithm
12 // for pseudo-random number generation. HepRandom defines a static private
13 // data member theGenerator and a set of static inlined methods to manipulate
14 // it. By means of theGenerator the user can change the underlying engine
15 // algorithm, get and set the seeds and use any kind of defined random
16 // distribution.
17 // Distribution classes inherit from HepRandom and define both static and
18 // not-static interfaces.
19 // A static table of uncorrelated seeds is available in this class.
20 // A static method "getTheTableSeeds()" is defined to access a couple of
21 // seeds at a given index in the table.
22
23 // =======================================================================
24 // Gabriele Cosmo - Created: 5th Sep 1995
25 // - Minor update: 17th May 1996
26 // - Poisson now operates on doubles : 31st Oct 1996
27 // - Added methods for engine status: 19th Nov 1996
28 // - Fixed default values to setTheSeed() and
29 // setTheSeeds() static methods: 16th Oct 1997
30 // - Modified HepRandom to act as a singleton, constructors
31 // are kept public for backward compatibility. Added table
32 // of seeds from HepRandomEngine: 19th Mar 1998
33 // - Relocated Poisson and Gauss data and simplified
34 // initialisation of static generator: 5th Jan 1999
35 // =======================================================================
36
37 #ifndef HepRandom_h
38 #define HepRandom_h 1
39
40 #include "CLHEP/Random/RandomEngine.h"
41
42 namespace CLHEP {
43
44 /**
45 * @author <Gabriele.Cosmo@cern.ch>
46 * @ingroup random
47 */
48 class HepRandom {
49
50 public:
51
52 HepRandom();
53 HepRandom(long seed);
54 // Contructors with and without a seed using the default engine
55 // (MixMax).
56
57 HepRandom(HepRandomEngine & algorithm);
58 HepRandom(HepRandomEngine * algorithm);
59 // Constructor taking an alternative engine as argument. If a pointer is
60 // given the corresponding object will be deleted by the HepRandom
61 // destructor.
62
63 virtual ~HepRandom();
64 // Destructor
65
66 // implicitly allow compiler-generated copy functions
67
68 double flat();
69 // Returns the flat value ( interval ]0...1[ ).
70
71 void flatArray(const int size, double* vect);
72 // Fills "vect" array of flat random values, given the size.
73
74 inline double flat (HepRandomEngine* theNewEngine);
75 // Returns a flat value, given a defined Random Engine.
76
77 inline void flatArray(HepRandomEngine* theNewEngine,
78 const int size, double* vect);
79 // Fills "vect" array of flat random values, given the size
80 // and a defined Random Engine.
81
82 virtual double operator()();
83 // To get a flat random number using the operator ().
84
85 virtual std::string name() const;
86 virtual HepRandomEngine & engine();
87
88
89 virtual std::ostream & put ( std::ostream & os ) const;
90 virtual std::istream & get ( std::istream & is );
91 // Save and restore to/from streams
92
93 // --------------------------------------------------
94 // Static member functions using the static generator
95 // --------------------------------------------------
96
97 static void setTheSeed(long seed, int lxr=3);
98 // (Re)Initializes the generator with a seed.
99
100 static long getTheSeed();
101 // Gets the current seed of the current generator.
102
103 static void setTheSeeds(const long* seeds, int aux=-1);
104 // (Re)Initializes the generator with a zero terminated list of seeds.
105
106 static const long* getTheSeeds();
107 // Gets the current array of seeds of the current generator.
108
109 static void getTheTableSeeds (long* seeds, int index);
110 // Gets the array of seeds in the static seedTable at "index" position.
111
112 static HepRandom * getTheGenerator();
113 // Return the current static generator.
114
115 static void setTheEngine (HepRandomEngine* theNewEngine);
116 // To set the underlying algorithm object.
117
118 static HepRandomEngine * getTheEngine();
119 // Returns a pointer to the underlying algorithm object.
120
121 static void saveEngineStatus( const char filename[] = "Config.conf" );
122 // Saves to file the current status of the current engine.
123
124 static void restoreEngineStatus( const char filename[] = "Config.conf" );
125 // Restores a saved status (if any) for the current engine.
126
127 static std::ostream& saveFullState ( std::ostream & os );
128 // Saves to stream the state of the engine and cached data.
129
130 static std::istream& restoreFullState ( std::istream & is );
131 // Restores from stream the state of the engine and cached data.
132
133 static std::ostream& saveDistState ( std::ostream & os ) {return os;}
134 // Saves to stream the state of the cached data.
135
136 static std::istream& restoreDistState ( std::istream & is ) {return is;}
137 // Restores from stream the state of the cached data.
138
139 static std::ostream& saveStaticRandomStates ( std::ostream & os );
140 // Saves to stream the engine and cached data for all distributions.
141
142 static std::istream& restoreStaticRandomStates ( std::istream & is );
143 // Restores from stream the engine and cached data for all distributions.
144
145 static void showEngineStatus();
146 // Dumps the current engine status on screen.
147
148 static int createInstance();
149 // used to initialise the default engine
150
151 static std::string distributionName() {return "HepRandomEngine";}
152 // Provides the name of this distribution class
153
154 protected: // -------- Data members ---------
155
156 static const long seedTable[215][2];
157 // Table of seeds
158
159 };
160
161 std::ostream & operator<< (std::ostream & os, const HepRandom & dist);
162 std::istream & operator>> (std::istream & is, HepRandom & dist);
163
164 } // namespace CLHEP
165
166 #include "CLHEP/Random/Random.icc"
167
168 #endif
169