| Geant4 Cross Reference |
1 // -*- C++ -*-
2 //
3 // -----------------------------------------------------------------------
4 // HEP Random
5 // --- RandExponential ---
6 // class header file
7 // -----------------------------------------------------------------------
8 // This file is part of Geant4 (simulation toolkit for HEP).
9 //
10 // Class defining methods for shooting exponential distributed random
11 // values, given a mean (default mean = 1).
12 // Default mean is used for operator()().
13
14 // =======================================================================
15 // Gabriele Cosmo - Created: 5th September 1995
16 // - Added methods to shoot arrays: 28th July 1997
17 // J.Marraffino - Added default mean as attribute and
18 // operator() with mean: 16th Feb 1998
19 // M Fischler - put and get to/from streams 12/10/04
20 // =======================================================================
21
22 #ifndef RandExponential_h
23 #define RandExponential_h 1
24
25 #include "CLHEP/Random/Random.h"
26 #include "CLHEP/Utility/memory.h"
27
28 namespace CLHEP {
29
30 /**
31 * @author <Gabriele.Cosmo@cern.ch>
32 * @ingroup random
33 */
34 class RandExponential : public HepRandom {
35
36 public:
37
38 inline RandExponential ( HepRandomEngine& anEngine, double mean=1.0 );
39 inline RandExponential ( HepRandomEngine* anEngine, double mean=1.0 );
40 // These constructors should be used to instantiate a RandExponential
41 // distribution object defining a local engine for it.
42 // The static generator will be skipped using the non-static methods
43 // defined below.
44 // If the engine is passed by pointer the corresponding engine object
45 // will be deleted by the RandExponential destructor.
46 // If the engine is passed by reference the corresponding engine object
47 // will not be deleted by the RandExponential destructor.
48
49 virtual ~RandExponential();
50 // Destructor
51
52 // Static methods to shoot random values using the static generator
53
54 static double shoot();
55
56 static double shoot( double mean );
57
58 static void shootArray ( const int size, double* vect,
59 double mean=1.0 );
60
61 // Static methods to shoot random values using a given engine
62 // by-passing the static generator.
63
64 static inline double shoot( HepRandomEngine* anEngine );
65
66 static inline double shoot( HepRandomEngine* anEngine, double mean );
67
68 static void shootArray ( HepRandomEngine* anEngine, const int size,
69 double* vect, double mean=1.0 );
70
71 // Methods using the localEngine to shoot random values, by-passing
72 // the static generator.
73
74 inline double fire();
75
76 inline double fire( double mean );
77
78 void fireArray ( const int size, double* vect );
79 void fireArray ( const int size, double* vect, double mean );
80
81 double operator()();
82 double operator()( double mean );
83
84 // Save and restore to/from streams
85
86 std::ostream & put ( std::ostream & os ) const;
87 std::istream & get ( std::istream & is );
88
89 std::string name() const;
90 HepRandomEngine & engine();
91
92 static std::string distributionName() {return "RandExponential";}
93 // Provides the name of this distribution class
94
95 private:
96
97 std::shared_ptr<HepRandomEngine> localEngine;
98 double defaultMean;
99
100 };
101
102 } // namespace CLHEP
103
104 #include "CLHEP/Random/RandExponential.icc"
105
106 #endif
107