| Geant4 Cross Reference |
1 // -*- C++ -*-
2 //
3 // -----------------------------------------------------------------------
4 // Hep Random
5 // --- DualRand ---
6 // class header file
7 // -----------------------------------------------------------------------
8 //
9 // Canopy random number generator DualRand
10 // Re-written as C++ routine for 32-bit ints MF 1/26/98
11 //
12 // Exclusive or of a feedback shift register and integer congruence
13 // random number generator. The feedback shift register uses offsets
14 // 127 and 97. The integer congruence generator uses a different
15 // multiplier for each stream. The multipliers are chosen to give
16 // full period and maximum "potency" for modulo 2^32. The period of
17 // the combined random number generator is 2^159 - 2^32, and the
18 // sequences are different for each stream (not just started in a
19 // different place).
20 //
21 // =======================================================================
22 // Canopy random number generator DualRand.
23 // Doug Toussaint 5/25/88
24 // Optimized by GMH 7/26/88
25 // Optimized by GMH 7/26/88
26 // Repaired by GMH 12/1/88 to update modular congruence state
27 // Put into ranlib by GMH 6/23/89
28 // Re-written as C++ routine for 32-bit ints MF 1/26/98
29 // Re-written for CLHEP package KLS 6/04/98
30 // Removed pow() from flat method for speed KLS 7/21/98
31 // Ken Smith - Added conversion operators: 6th Aug 1998
32 // Mark Fischler methods for distrib. instance save/restore 12/8/04
33 // Mark Fischler methods for anonymous save/restore 12/27/04
34 // Mark Fischler - methods for vector save/restore 3/7/05
35 // =======================================================================
36
37
38 #ifndef DualRand_h
39 #define DualRand_h
40
41 #include "CLHEP/Random/RandomEngine.h"
42
43 namespace CLHEP {
44
45 /**
46 * @author
47 * @ingroup random
48 */
49 class DualRand: public HepRandomEngine {
50
51 public:
52
53 DualRand();
54 DualRand(long seed);
55 DualRand(std::istream & is);
56 DualRand(int rowIndex, int colIndex);
57 virtual ~DualRand();
58
59 // let the compiler generate the copy constructors
60 //DualRand(const DualRand & p);
61 //DualRand & operator=(const DualRand & p);
62
63 double flat();
64 // Returns a pseudo random number between 0 and 1
65 // (excluding the end points)
66
67 void flatArray(const int size, double * vect);
68 // Fills an array "vect" of specified size with flat random values.
69
70 void setSeed(long seed, int);
71 // Sets the state of the algorithm according to seed.
72
73 void setSeeds(const long * seeds, int);
74 // Sets the state of the algorithm according to the zero-terminated
75 // array of seeds.
76
77 void saveStatus( const char filename[] = "DualRand.conf") const;
78 // Saves on named file the current engine status.
79
80 void restoreStatus( const char filename[] = "DualRand.conf" );
81 // Reads from named file the last saved engine status and restores it.
82
83 void showStatus() const;
84 // Dumps the current engine status on the screen.
85
86 operator double(); // Returns same as flat()
87 operator float(); // flat value, without worrying about filling bits
88 operator unsigned int(); // 32-bit flat value, quickest of all
89
90 virtual std::ostream & put (std::ostream & os) const;
91 virtual std::istream & get (std::istream & is);
92 static std::string beginTag ( );
93 virtual std::istream & getState ( std::istream & is );
94
95 std::string name() const;
96 static std::string engineName() {return "DualRand";}
97
98 std::vector<unsigned long> put () const;
99 bool get (const std::vector<unsigned long> & v);
100 bool getState (const std::vector<unsigned long> & v);
101
102 static const unsigned int VECTOR_STATE_SIZE = 9;
103
104 private:
105
106 // This generator is composed of two others combined:
107
108 class Tausworthe {
109 public:
110 Tausworthe();
111 Tausworthe(unsigned int seed);
112 operator unsigned int();
113 void put(std::ostream & os) const;
114 void put(std::vector<unsigned long> & v) const;
115 void get(std::istream & is);
116 bool get(std::vector<unsigned long>::const_iterator & iv);
117 private:
118 int wordIndex;
119 unsigned int words[4];
120 }; // Tausworthe
121
122 class IntegerCong {
123 public:
124 IntegerCong();
125 IntegerCong(unsigned int seed, int streamNumber);
126 operator unsigned int();
127 void put(std::ostream & os) const;
128 void put(std::vector<unsigned long> & v) const;
129 void get(std::istream & is);
130 bool get(std::vector<unsigned long>::const_iterator & iv);
131 private:
132 unsigned int state, multiplier, addend;
133 }; // IntegerCong
134
135 int numEngines;
136 Tausworthe tausworthe;
137 IntegerCong integerCong;
138
139 }; // DualRand
140
141 } // namespace CLHEP
142
143 #endif // DualRand_h
144