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GRan.hpp
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1 /***************************************************************************
2  * GRan.hpp - Random number generator class *
3  * ----------------------------------------------------------------------- *
4  * copyright (C) 2011-2014 by Juergen Knoedlseder *
5  * ----------------------------------------------------------------------- *
6  * *
7  * This program is free software: you can redistribute it and/or modify *
8  * it under the terms of the GNU General Public License as published by *
9  * the Free Software Foundation, either version 3 of the License, or *
10  * (at your option) any later version. *
11  * *
12  * This program is distributed in the hope that it will be useful, *
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of *
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
15  * GNU General Public License for more details. *
16  * *
17  * You should have received a copy of the GNU General Public License *
18  * along with this program. If not, see <http://www.gnu.org/licenses/>. *
19  * *
20  ***************************************************************************/
21 /**
22  * @file GRan.hpp
23  * @brief Random number generator class definition
24  * @author Juergen Knoedlseder
25  */
26 
27 #ifndef GRAN_HPP
28 #define GRAN_HPP
29 
30 /* __ Includes ___________________________________________________________ */
31 #include <string>
32 #include <vector>
33 #include "GBase.hpp"
34 #include "GVector.hpp"
35 
36 
37 /***********************************************************************//**
38  * @class GRan
39  *
40  * @brief Random number generator class
41  *
42  * This class implements a random number generator.
43  ***************************************************************************/
44 class GRan : public GBase {
45 
46 public:
47  // Constructors and destructors
48  GRan(void);
49  GRan(unsigned long long int seed);
50  GRan(const GRan& ran);
51  virtual ~GRan(void);
52 
53  // Operators
54  GRan& operator=(const GRan& ran);
55 
56  // Methods
57  void clear(void);
58  GRan* clone(void) const;
59  std::string classname(void) const;
60  void seed(unsigned long long int seed);
61  unsigned long long int seed(void) const;
62  unsigned long int int32(void);
63  unsigned long long int int64(void);
64  double uniform(void);
65  double normal(void);
66  double exp(const double& lambda);
67  double poisson(const double& lambda);
68  double chisq2(void);
69  int cdf(const std::vector<double>& cdf);
70  int cdf(const GVector& cdf);
71  std::string print(const GChatter& chatter = NORMAL) const;
72 
73 protected:
74  // Protected methods
75  void init_members(unsigned long long int seed = 41L);
76  void copy_members(const GRan& ran);
77  void free_members(void);
78 
79  // Protected data members
80  unsigned long long int m_seed; //!< Random number generator seed
81  unsigned long long int m_value1; //!< Value 1
82  unsigned long long int m_value2; //!< Value 2
83  unsigned long long int m_value3; //!< Value 3
84 
85  // Poisson cache
86  double m_old_lambda; //!< Old lambda value
87  double m_sqrt_lambda; //!< sqrt(2*lambda)
88  double m_log_lambda; //!< log(lambda)
89  double m_exp_lambda; //!< exp(-lambda)
90 };
91 
92 
93 /***********************************************************************//**
94  * @brief Return class name
95  *
96  * @return String containing the class name ("GRan").
97  ***************************************************************************/
98 inline
99 std::string GRan::classname(void) const
100 {
101  return ("GRan");
102 }
103 
104 
105 /***********************************************************************//**
106  * @brief Return seed value
107  *
108  * @return Seed value.
109  ***************************************************************************/
110 inline
111 unsigned long long int GRan::seed(void) const
112 {
113  return m_seed;
114 }
115 
116 #endif /* GRAN_HPP */
double chisq2(void)
Returns Chi2 deviates for 2 degrees of freedom.
Definition: GRan.cpp:370
double m_exp_lambda
exp(-lambda)
Definition: GRan.hpp:89
std::string print(const GChatter &chatter=NORMAL) const
Print random number generator information.
Definition: GRan.cpp:451
double m_sqrt_lambda
sqrt(2*lambda)
Definition: GRan.hpp:87
unsigned long long int int64(void)
Return 64-bit random unsigned integer.
Definition: GRan.cpp:216
void copy_members(const GRan &ran)
Copy class members.
Definition: GRan.cpp:513
GRan(void)
Void constructor.
Definition: GRan.cpp:57
int cdf(const std::vector< double > &cdf)
Random sampling from a cumulative density function.
Definition: GRan.cpp:390
Definition of interface for all GammaLib classes.
unsigned long long int m_value2
Value 2.
Definition: GRan.hpp:82
Random number generator class.
Definition: GRan.hpp:44
void free_members(void)
Delete class members.
Definition: GRan.cpp:533
double m_old_lambda
Old lambda value.
Definition: GRan.hpp:86
unsigned long long int m_value1
Value 1.
Definition: GRan.hpp:81
unsigned long int int32(void)
Return 32-bit random unsigned integer.
Definition: GRan.cpp:206
Interface class for all GammaLib classes.
Definition: GBase.hpp:52
unsigned long long int m_value3
Value 3.
Definition: GRan.hpp:83
double uniform(void)
Returns random double precision floating value in range 0 to 1.
Definition: GRan.cpp:242
GRan * clone(void) const
Clone random number generator.
Definition: GRan.cpp:176
unsigned long long int seed(void) const
Return seed value.
Definition: GRan.hpp:111
GChatter
Definition: GTypemaps.hpp:33
Vector class interface definition.
double normal(void)
Returns normal deviates.
Definition: GRan.cpp:257
unsigned long long int m_seed
Random number generator seed.
Definition: GRan.hpp:80
void init_members(unsigned long long int seed=41L)
Initialise class members.
Definition: GRan.cpp:484
GRan & operator=(const GRan &ran)
Assignment operator.
Definition: GRan.cpp:125
virtual ~GRan(void)
Destructor.
Definition: GRan.cpp:103
double m_log_lambda
log(lambda)
Definition: GRan.hpp:88
double poisson(const double &lambda)
Returns Poisson deviates.
Definition: GRan.cpp:316
std::string classname(void) const
Return class name.
Definition: GRan.hpp:99
void clear(void)
Clear random number generator.
Definition: GRan.cpp:158
Vector class.
Definition: GVector.hpp:46
double exp(const double &lambda)
Returns exponential deviates.
Definition: GRan.cpp:291