mdtools/md_code/randomSPRNG.cpp

#include <iostream>
#include <cmath>

#include "randomSPRNG.hpp"
#include "simError.h"
#include "sprng.h"

#ifdef IS_MPI
#include "mpiSimulation.hpp"
#endif

using namespace std;

/* randomStreamSPRNF creates a new SPRNG stream for random numbers
 */

int randomSPRNG::nStreamsInitialized = 0;

randomSPRNG::randomSPRNG(int iseed){
  int newSeed;
  nStreamsInitialized++;
  newSeed = abs(iseed) + nStreamsInitialized;  
  if( newSeed < 0 ) newSeed = abs( newSeed );

#ifdef IS_MPI

  nSPRNGStreams = mpiSim->getNumberProcessors();
 
  myStreamNumber = mpiSim->getMyNode();

  
#else

  nSPRNGStreams = 1;
  myStreamNumber = 0;

#endif


  thisStream = init_sprng(GTYPE,myStreamNumber,nSPRNGStreams,
                         newSeed,SPRNG_DEFAULT);
}

randomSPRNG::~randomSPRNG(){
  if ( thisStream != NULL){
    free_sprng(thisStream);
    nStreamsInitialized--;
  }
}


double randomSPRNG::getRandom(){
  return sprng(thisStream);
}


// Gaussian SPRNG class...

double gaussianSPRNG::getGaussian(){
  double ranNum1;
  double ranNum2;
  double gaussianNumber;

  ranNum1 = getRandom();
  ranNum2 = getRandom();

  gaussianNumber = sqrt(-2.0 * log(ranNum1)) * cos(2 * M_PI * ranNum2);

  return gaussianNumber;
}
Revision:	253
Committed:	Thu Jan 30 15:20:21 2003 UTC (22 years, 9 months ago) by chuckv
File size:	1194 byte(s)
Log Message:	Added a generic util code directory and moved Linux_ifc_machdep to it. MPI changes to compile MPI modules.
#	User	Rev	Content
1	chuckv	219	#include <iostream>
2			#include <cmath>
3
4			#include "randomSPRNG.hpp"
5			#include "simError.h"
6	chuckv	223	#include "sprng.h"
7
8	chuckv	221	#ifdef IS_MPI
9			#include "mpiSimulation.hpp"
10			#endif
11	chuckv	219
12	chuckv	253	using namespace std;
13
14	chuckv	220	/* randomStreamSPRNF creates a new SPRNG stream for random numbers
15			*/
16	chuckv	219
17	chuckv	223	int randomSPRNG::nStreamsInitialized = 0;
18	chuckv	219
19	chuckv	250	randomSPRNG::randomSPRNG(int iseed){
20	chuckv	223	int newSeed;
21	chuckv	221	nStreamsInitialized++;
22	chuckv	223	newSeed = abs(iseed) + nStreamsInitialized;
23			if( newSeed < 0 ) newSeed = abs( newSeed );
24	chuckv	219
25	chuckv	223	#ifdef IS_MPI
26	chuckv	220
27	chuckv	223	nSPRNGStreams = mpiSim->getNumberProcessors();
28
29			myStreamNumber = mpiSim->getMyNode();
30
31
32
33	chuckv	220	#else
34	chuckv	223
35	chuckv	221	nSPRNGStreams = 1;
36	chuckv	253	myStreamNumber = 0;
37	chuckv	220
38	chuckv	221	#endif
39	chuckv	220
40	chuckv	253
41	chuckv	221	thisStream = init_sprng(GTYPE,myStreamNumber,nSPRNGStreams,
42	chuckv	253	newSeed,SPRNG_DEFAULT);
43	chuckv	219	}
44	chuckv	220
45	chuckv	221	randomSPRNG::~randomSPRNG(){
46	chuckv	252	if ( thisStream != NULL){
47	chuckv	253	free_sprng(thisStream);
48	chuckv	252	nStreamsInitialized--;
49			}
50	chuckv	220	}
51
52
53	chuckv	221	double randomSPRNG::getRandom(){
54	chuckv	223	return sprng(thisStream);
55	chuckv	220	}
56	chuckv	221
57
58			// Gaussian SPRNG class...
59
60			double gaussianSPRNG::getGaussian(){
61			double ranNum1;
62			double ranNum2;
63			double gaussianNumber;
64
65			ranNum1 = getRandom();
66			ranNum2 = getRandom();
67
68			gaussianNumber = sqrt(-2.0 * log(ranNum1)) * cos(2 * M_PI * ranNum2);
69
70			return gaussianNumber;
71			}