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