| Geant4 Cross Reference |
1 // -*- C++ -*-
2 //
3 // -----------------------------------------------------------------------
4 // HEP Random
5 // --- RandBinomial ---
6 // class header file
7 // -----------------------------------------------------------------------
8
9 // Class defining methods for shooting binomial distributed random values,
10 // given a sample size n (default=1) and a probability p (default=0.5).
11 // Default values are used for operator()().
12 //
13 // Valid input values satisfy the relation n*min(p,1-p) > 0. When invalid
14 // values are presented, the code silently returns -1.0.
15
16 // =======================================================================
17 // John Marraffino - Created: 12th May 1998 Based on the C-Rand package
18 // by Ernst Stadlober and Franz Niederl of the Technical
19 // University of Graz, Austria.
20 // Gabriele Cosmo - Removed useless methods and data: 5th Jan 1999
21 // M Fischler - put and get to/from streams 12/10/04
22 // =======================================================================
23
24 #ifndef RandBinomial_h
25 #define RandBinomial_h 1
26
27 #include "CLHEP/Random/Random.h"
28 #include "CLHEP/Utility/memory.h"
29
30 namespace CLHEP {
31
32 /**
33 * @author
34 * @ingroup random
35 */
36 class RandBinomial : public HepRandom {
37
38 public:
39
40 inline RandBinomial ( HepRandomEngine& anEngine, long n=1,
41 double p=0.5 );
42 inline RandBinomial ( HepRandomEngine* anEngine, long n=1,
43 double p=0.5 );
44 // These constructors should be used to instantiate a RandBinomial
45 // distribution object defining a local engine for it.
46 // The static generator will be skipped using the non-static methods
47 // defined below.
48 // If the engine is passed by pointer the corresponding engine object
49 // will be deleted by the RandBinomial destructor.
50 // If the engine is passed by reference the corresponding engine object
51 // will not be deleted by the RandBinomial destructor.
52
53 virtual ~RandBinomial();
54 // Destructor
55
56 // Static methods to shoot random values using the static generator
57
58 static inline double shoot();
59
60 static double shoot( long n, double p );
61
62 static void shootArray ( const int size, double* vect,
63 long n=1, double p=0.5 );
64
65 // Static methods to shoot random values using a given engine
66 // by-passing the static generator.
67
68 static inline double shoot( HepRandomEngine* anEngine );
69
70 static double shoot( HepRandomEngine* anEngine,
71 long n, double p );
72
73 static void shootArray ( HepRandomEngine* anEngine, const int size,
74 double* vect, long n=1,
75 double p=0.5 );
76
77 // Methods using the localEngine to shoot random values, by-passing
78 // the static generator.
79
80 inline double fire();
81
82 double fire( long n, double p );
83
84 void fireArray ( const int size, double* vect);
85 void fireArray ( const int size, double* vect,
86 long n, double p );
87 inline double operator()();
88 inline double operator()( long n, double p );
89
90 // Save and restore to/from streams
91
92 std::ostream & put ( std::ostream & os ) const;
93 std::istream & get ( std::istream & is );
94
95 std::string name() const;
96 HepRandomEngine & engine();
97
98 static std::string distributionName() {return "RandBinomial";}
99 // Provides the name of this distribution class
100
101 private:
102
103 static double genBinomial( HepRandomEngine *anEngine, long n, double p );
104
105 std::shared_ptr<HepRandomEngine> localEngine;
106 long defaultN;
107 double defaultP;
108
109 };
110
111 } // namespace CLHEP
112
113 #include "CLHEP/Random/RandBinomial.icc"
114
115 #endif
116