SST 12.1.0 Structural Simulation Toolkit
poisson.h
1// Copyright 2009-2022 NTESS. Under the terms
2// of Contract DE-NA0003525 with NTESS, the U.S.
3// Government retains certain rights in this software.
4//
5// Copyright (c) 2009-2022, NTESS
7//
8// This file is part of the SST software package. For license
9// information, see the LICENSE file in the top level directory of the
10// distribution.
11
12#ifndef SST_CORE_RNG_POISSON_H
13#define SST_CORE_RNG_POISSON_H
14
15#include "distrib.h"
16#include "math.h"
17#include "mersenne.h"
18#include "rng.h"
19
20using namespace SST::RNG;
21
22namespace SST {
23namespace RNG {
24
25/**
26 \class PoissonDistribution poisson.h "sst/core/rng/poisson.h"
27
28 Creates an Poisson distribution for use within SST. This distribution is the same across
29 platforms and compilers.
30*/
32{
33
34public:
35 /**
36 Creates an Poisson distribution with a specific lambda
37 \param mn The lambda of the Poisson distribution
38 */
40 {
41
43 deleteDistrib = true;
44 }
45
46 /**
47 Creates an Poisson distribution with a specific lambda and a base random number generator
48 \param lambda The lambda of the Poisson distribution
49 \param baseDist The base random number generator to take the distribution from.
50 */
52 {
53
54 baseDistrib = baseDist;
55 deleteDistrib = false;
56 }
57
58 /**
59 Destroys the Poisson distribution
60 */
62 {
63 if ( deleteDistrib ) { delete baseDistrib; }
64 }
65
66 /**
67 Gets the next (random) double value in the distribution
68 \return The next random double from the distribution
69 */
71 {
72 const double L = exp(-lambda);
73 double p = 1.0;
74 int k = 0;
75
76 do {
77 k++;
79 } while ( p > L );
80
81 return k - 1;
82 }
83
84 /**
85 Gets the lambda with which the distribution was created
86 \return The lambda which the user created the distribution with
87 */
88 double getLambda() { return lambda; }
89
90protected:
91 /**
92 Sets the lambda of the Poisson distribution.
93 */
94 const double lambda;
95 /**
96 Sets the base random number generator for the distribution.
97 */
99
100 /**
101 Controls whether the base distribution should be deleted when this class is destructed.
102 */
104};
105
107
108} // namespace RNG
109} // namespace SST
110
111#endif // SST_CORE_RNG_POISSON_H
Implements a Mersenne-based RNG for use in the SST core or components.
Definition: mersenne.h:35
Creates an Poisson distribution for use within SST.
Definition: poisson.h:32
double getNextDouble()
Gets the next (random) double value in the distribution.
Definition: poisson.h:70
~PoissonDistribution()
Destroys the Poisson distribution.
Definition: poisson.h:61
PoissonDistribution(const double mn, SST::RNG::Random *baseDist)
Creates an Poisson distribution with a specific lambda and a base random number generator.
Definition: poisson.h:51
const double lambda
Sets the lambda of the Poisson distribution.
Definition: poisson.h:94
double getLambda()
Gets the lambda with which the distribution was created.
Definition: poisson.h:88
SST::RNG::Random * baseDistrib
Sets the base random number generator for the distribution.
Definition: poisson.h:98
bool deleteDistrib
Controls whether the base distribution should be deleted when this class is destructed.
Definition: poisson.h:103
PoissonDistribution(const double mn)
Creates an Poisson distribution with a specific lambda.
Definition: poisson.h:39
Base class of statistical distributions in SST.
Definition: distrib.h:23
Implements the base class for random number generators for the SST core.
Definition: rng.h:28
virtual double nextUniform()=0
Generates the next random number in the range [0,1).