| Geant4 Cross Reference |
1 // -*- C++ -*-
2 //
3 // -----------------------------------------------------------------------
4 // HEP Random
5 // --- RanluxEngine ---
6 // class header file
7 // -----------------------------------------------------------------------
8 // This file is part of Geant4 (simulation toolkit for HEP).
9 //
10 // The algorithm for this random engine has been taken from the original
11 // implementation in FORTRAN by Fred James as part of the MATHLIB HEP
12 // library.
13 // The initialisation is carried out using a Multiplicative Congruential
14 // generator using formula constants of L'Ecuyer as described in "F.James,
15 // Comp. Phys. Comm. 60 (1990) 329-344".
16
17 // =======================================================================
18 // Adeyemi Adesanya - Created: 6th November 1995
19 // Gabriele Cosmo - Adapted & Revised: 22nd November 1995
20 // Adeyemi Adesanya - Added setSeeds() method: 2nd February 1996
21 // Gabriele Cosmo - Added flatArray() method: 8th February 1996
22 // - Added methods for engine status: 19th November 1996
23 // - Added default luxury value for setSeed()
24 // and setSeeds(): 21st July 1997
25 // J.Marraffino - Added stream operators and related constructor.
26 // Added automatic seed selection from seed table and
27 // engine counter: 14th Feb 1998
28 // Ken Smith - Added conversion operators: 6th Aug 1998
29 // Mark Fischler Methods put, get for instance save/restore 12/8/04
30 // Mark Fischler methods for anonymous save/restore 12/27/04
31 // =======================================================================
32
33 #ifndef RanluxEngine_h
34 #define RanluxEngine_h 1
35
36 #include "CLHEP/Random/RandomEngine.h"
37
38 namespace CLHEP {
39
40 /**
41 * @author
42 * @ingroup random
43 */
44 class RanluxEngine : public HepRandomEngine {
45
46 public:
47
48 RanluxEngine( std::istream& is );
49 RanluxEngine();
50 RanluxEngine( long seed, int lxr = 3 );
51 RanluxEngine( int rowIndex, int colIndex, int lxr );
52 virtual ~RanluxEngine();
53 // Constructors and destructor
54
55 // Luxury level is set in the same way as the original FORTRAN routine.
56 // level 0 (p=24): equivalent to the original RCARRY of Marsaglia
57 // and Zaman, very long period, but fails many tests.
58 // level 1 (p=48): considerable improvement in quality over level 0,
59 // now passes the gap test, but still fails spectral test.
60 // level 2 (p=97): passes all known tests, but theoretically still
61 // defective.
62 // level 3 (p=223): DEFAULT VALUE. Any theoretically possible
63 // correlations have very small chance of being observed.
64 // level 4 (p=389): highest possible luxury, all 24 bits chaotic.
65
66 double flat();
67 // It returns a pseudo random number between 0 and 1,
68 // excluding the end points.
69
70 void flatArray (const int size, double* vect);
71 // Fills the array "vect" of specified size with flat random values.
72
73 void setSeed(long seed, int lxr=3);
74 // Sets the state of the algorithm according to seed.
75
76 void setSeeds(const long * seeds, int lxr=3);
77 // Sets the state of the algorithm according to the zero terminated
78 // array of seeds. Only the first seed is used.
79
80 void saveStatus( const char filename[] = "Ranlux.conf" ) const;
81 // Saves on file Ranlux.conf the current engine status.
82
83 void restoreStatus( const char filename[] = "Ranlux.conf" );
84 // Reads from file Ranlux.conf the last saved engine status
85 // and restores it.
86
87 void showStatus() const;
88 // Dumps the engine status on the screen.
89
90 int getLuxury() const { return luxury; }
91 // Gets the luxury level.
92
93 operator double(); // Returns same as flat()
94 operator float(); // less precise flat, faster if possible
95 operator unsigned int(); // 32-bit flat, but slower than double or float
96
97 virtual std::ostream & put (std::ostream & os) const;
98 virtual std::istream & get (std::istream & is);
99 static std::string beginTag ( );
100 virtual std::istream & getState ( std::istream & is );
101
102 std::string name() const;
103 static std::string engineName() {return "RanluxEngine";}
104
105 std::vector<unsigned long> put () const;
106 bool get (const std::vector<unsigned long> & v);
107 bool getState (const std::vector<unsigned long> & v);
108
109 static const unsigned int VECTOR_STATE_SIZE = 31;
110
111 private:
112
113 int nskip, luxury;
114 float float_seed_table[24];
115 int i_lag,j_lag;
116 float carry;
117 int count24;
118 static const int int_modulus = 0x1000000;
119 };
120
121 } // namespace CLHEP
122
123 #endif
124