CLHEP::RandGamma Class Reference

#include <RandGamma.h>

Inheritance diagram for CLHEP::RandGamma:

Public Member Functions
HepRandomEngine &	engine ()
double	fire ()
double	fire (double k, double lambda)
void	fireArray (const int size, double *vect)
void	fireArray (const int size, double *vect, double k, double lambda)
double	flat ()
double	flat (HepRandomEngine *theNewEngine)
void	flatArray (const int size, double *vect)
void	flatArray (HepRandomEngine *theNewEngine, const int size, double *vect)
std::istream &	get (std::istream &is)
std::string	name () const
double	operator() ()
double	operator() (double k, double lambda)
std::ostream &	put (std::ostream &os) const
	RandGamma (HepRandomEngine &anEngine, double k=1.0, double lambda=1.0)
	RandGamma (HepRandomEngine *anEngine, double k=1.0, double lambda=1.0)
virtual	~RandGamma ()

Static Public Member Functions
static int	createInstance ()
static std::string	distributionName ()
static HepRandomEngine *	getTheEngine ()
static HepRandom *	getTheGenerator ()
static long	getTheSeed ()
static const long *	getTheSeeds ()
static void	getTheTableSeeds (long *seeds, int index)
static std::istream &	restoreDistState (std::istream &is)
static void	restoreEngineStatus (const char filename[]="Config.conf")
static std::istream &	restoreFullState (std::istream &is)
static std::istream &	restoreStaticRandomStates (std::istream &is)
static std::ostream &	saveDistState (std::ostream &os)
static void	saveEngineStatus (const char filename[]="Config.conf")
static std::ostream &	saveFullState (std::ostream &os)
static std::ostream &	saveStaticRandomStates (std::ostream &os)
static void	setTheEngine (HepRandomEngine *theNewEngine)
static void	setTheSeed (long seed, int lxr=3)
static void	setTheSeeds (const long *seeds, int aux=-1)
static double	shoot ()
static double	shoot (double k, double lambda)
static double	shoot (HepRandomEngine *anEngine)
static double	shoot (HepRandomEngine *anEngine, double k, double lambda)
static void	shootArray (const int size, double *vect, double k=1.0, double lambda=1.0)
static void	shootArray (HepRandomEngine *anEngine, const int size, double *vect, double k=1.0, double lambda=1.0)
static void	showEngineStatus ()

Static Protected Attributes
static const long	seedTable [215][2]

Static Private Member Functions
static double	genGamma (HepRandomEngine *anEngine, double k, double lambda)

Private Attributes
double	defaultK
double	defaultLambda
std::shared_ptr< HepRandomEngine >	localEngine

Detailed Description

Author

Definition at line 36 of file RandGamma.h.

Constructor & Destructor Documentation

RandGamma() [1/2]

CLHEP::RandGamma::RandGamma ( HepRandomEngine &  anEngine, double  k = 1.0, double  lambda = 1.0  )

inline

RandGamma() [2/2]

CLHEP::RandGamma::RandGamma ( HepRandomEngine *  anEngine, double  k = 1.0, double  lambda = 1.0  )

inline

~RandGamma()

CLHEP::RandGamma::~RandGamma ( )

virtual

Definition at line 30 of file RandGamma.cc.

                      {
}

Member Function Documentation

createInstance()

int CLHEP::HepRandom::createInstance ( )

staticinherited

Definition at line 311 of file Random.cc.

{
  return static_cast<int>( theDefaults().ensureInitialized() );
}

References CLHEP::anonymous_namespace{Random.cc}::defaults::ensureInitialized(), and CLHEP::anonymous_namespace{Random.cc}::theDefaults().

distributionName()

static std::string CLHEP::RandGamma::distributionName ( )

inlinestatic

Definition at line 98 of file RandGamma.h.

{return "RandGamma";}  

engine()

HepRandomEngine & CLHEP::RandGamma::engine ( )

virtual

Reimplemented from CLHEP::HepRandom.

Definition at line 28 of file RandGamma.cc.

{return *localEngine;}

References localEngine.

fire() [1/2]

double CLHEP::RandGamma::fire ( )

inline

Referenced by fireArray().

fire() [2/2]

double CLHEP::RandGamma::fire	(	double	k,
		double	lambda
	)

Definition at line 43 of file RandGamma.cc.

                                                {
  return genGamma( localEngine.get(), k, lambda );
}

References genGamma(), G4InuclParticleNames::lambda, and localEngine.

fireArray() [1/2]

void CLHEP::RandGamma::fireArray	(	const int	size,
		double *	vect
	)

Definition at line 62 of file RandGamma.cc.

{
  for( double* v = vect; v != vect + size; ++v )
    *v = fire(defaultK,defaultLambda);
}

References defaultK, defaultLambda, and fire().

fireArray() [2/2]

void CLHEP::RandGamma::fireArray	(	const int	size,
		double *	vect,
		double	k,
		double	lambda
	)

Definition at line 68 of file RandGamma.cc.

{
  for( double* v = vect; v != vect + size; ++v )
    *v = fire(k,lambda);
}

References fire(), and G4InuclParticleNames::lambda.

flat() [1/2]

double CLHEP::HepRandom::flat ( )

inherited

Definition at line 199 of file Random.cc.

{
  return theDefaults().theEngine->flat();
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

Referenced by CLHEP::RandExponential::shoot().

flat() [2/2]

double CLHEP::HepRandom::flat ( HepRandomEngine *  theNewEngine )

inlineinherited

flatArray() [1/2]

void CLHEP::HepRandom::flatArray ( const int  size, double *  vect  )

inherited

Definition at line 204 of file Random.cc.

{
  theDefaults().theEngine->flatArray(size,vect);
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

flatArray() [2/2]

void CLHEP::HepRandom::flatArray ( HepRandomEngine *  theNewEngine, const int  size, double *  vect  )

inlineinherited

genGamma()

double CLHEP::RandGamma::genGamma ( HepRandomEngine *  anEngine, double  k, double  lambda  )

staticprivate

Definition at line 75 of file RandGamma.cc.

                                                         {
/*************************************************************************
 *         Gamma Distribution - Rejection algorithm gs combined with     *
 *                              Acceptance complement method gd          *
 *************************************************************************/
 
  static CLHEP_THREAD_LOCAL double aa = -1.0, aaa = -1.0, b, c, d, e, r, s, si, ss, q0;
  static const double q1 = 0.0416666664, q2 =  0.0208333723, q3 = 0.0079849875,
       q4 = 0.0015746717, q5 = -0.0003349403, q6 = 0.0003340332,
       q7 = 0.0006053049, q8 = -0.0004701849, q9 = 0.0001710320,
       a1 = 0.333333333,  a2 = -0.249999949,  a3 = 0.199999867,
       a4 =-0.166677482,  a5 =  0.142873973,  a6 =-0.124385581,
       a7 = 0.110368310,  a8 = -0.112750886,  a9 = 0.104089866,
       e1 = 1.000000000,  e2 =  0.499999994,  e3 = 0.166666848,
       e4 = 0.041664508,  e5 =  0.008345522,  e6 = 0.001353826,
       e7 = 0.000247453;
 
double gds,p,q,t,sign_u,u,v,w,x;
double v1,v2,v12;
 
// Check for invalid input values
 
 if( a <= 0.0 ) return (-1.0);
 if( lambda <= 0.0 ) return (-1.0);
 
 if (a < 1.0)
   {          // CASE A: Acceptance rejection algorithm gs
    b = 1.0 + 0.36788794412 * a;       // Step 1
    for(;;)
      {
       p = b * anEngine->flat();
       if (p <= 1.0)
      {                            // Step 2. Case gds <= 1
       gds = std::exp(std::log(p) / a);
       if (std::log(anEngine->flat()) <= -gds) return(gds/lambda);
      }
       else
      {                            // Step 3. Case gds > 1
       gds = - std::log ((b - p) / a);
       if (std::log(anEngine->flat()) <= ((a - 1.0) * std::log(gds))) return(gds/lambda);
      }
      }
   }
 else
   {          // CASE B: Acceptance complement algorithm gd
    if (a != aa)
       {                               // Step 1. Preparations
    aa = a;
    ss = a - 0.5;
    s = std::sqrt(ss);
    d = 5.656854249 - 12.0 * s;
       }
                                              // Step 2. Normal deviate
    do {
      v1 = 2.0 * anEngine->flat() - 1.0;
      v2 = 2.0 * anEngine->flat() - 1.0;
      v12 = v1*v1 + v2*v2;
    } while ( v12 > 1.0 );
    t = v1*std::sqrt(-2.0*std::log(v12)/v12);
    x = s + 0.5 * t;
    gds = x * x;
    if (t >= 0.0) return(gds/lambda);         // Immediate acceptance
 
    u = anEngine->flat();            // Step 3. Uniform random number
    if (d * u <= t * t * t) return(gds/lambda); // Squeeze acceptance
 
    if (a != aaa)
       {                               // Step 4. Set-up for hat case
    aaa = a;
    r = 1.0 / a;
    q0 = ((((((((q9 * r + q8) * r + q7) * r + q6) * r + q5) * r + q4) *
              r + q3) * r + q2) * r + q1) * r;
    if (a > 3.686)
       {
        if (a > 13.022)
           {
        b = 1.77;
        si = 0.75;
        c = 0.1515 / s;
           }
        else
           {
        b = 1.654 + 0.0076 * ss;
        si = 1.68 / s + 0.275;
        c = 0.062 / s + 0.024;
           }
       }
    else
       {
        b = 0.463 + s - 0.178 * ss;
        si = 1.235;
        c = 0.195 / s - 0.079 + 0.016 * s;
       }
       }
    if (x > 0.0)                       // Step 5. Calculation of q
       {
    v = t / (s + s);               // Step 6.
    if (std::fabs(v) > 0.25)
       {
        q = q0 - s * t + 0.25 * t * t + (ss + ss) * std::log(1.0 + v);
       }
    else
       {
        q = q0 + 0.5 * t * t * ((((((((a9 * v + a8) * v + a7) * v + a6) *
                v + a5) * v + a4) * v + a3) * v + a2) * v + a1) * v;
       }                // Step 7. Quotient acceptance
    if (std::log(1.0 - u) <= q) return(gds/lambda);
       }
 
    for(;;)
       {                    // Step 8. Double exponential deviate t
    do
    {
     e = -std::log(anEngine->flat());
     u = anEngine->flat();
     u = u + u - 1.0;
     sign_u = (u > 0)? 1.0 : -1.0;
     t = b + (e * si) * sign_u;
    }
    while (t <= -0.71874483771719);   // Step 9. Rejection of t
    v = t / (s + s);                  // Step 10. New q(t)
    if (std::fabs(v) > 0.25)
       {
        q = q0 - s * t + 0.25 * t * t + (ss + ss) * std::log(1.0 + v);
       }
    else
       {
        q = q0 + 0.5 * t * t * ((((((((a9 * v + a8) * v + a7) * v + a6) *
                v + a5) * v + a4) * v + a3) * v + a2) * v + a1) * v;
       }
    if (q <= 0.0) continue;           // Step 11.
    if (q > 0.5)
       {
        w = std::exp(q) - 1.0;
       }
    else
       {
        w = ((((((e7 * q + e6) * q + e5) * q + e4) * q + e3) * q + e2) *
                     q + e1) * q;
       }                    // Step 12. Hat acceptance
    if ( c * u * sign_u <= w * std::exp(e - 0.5 * t * t))
       {
        x = s + 0.5 * t;
        return(x*x/lambda);
       }
       }
   }
}

References CLHEP_THREAD_LOCAL, e1, e2, e3, e4, e5, e6, CLHEP::HepRandomEngine::flat(), G4InuclParticleNames::lambda, and CLHEP::s.

Referenced by fire(), and shoot().

get()

std::istream & CLHEP::RandGamma::get ( std::istream &  is )

virtual

Reimplemented from CLHEP::HepRandom.

Definition at line 238 of file RandGamma.cc.

                                              {
  std::string inName;
  is >> inName;
  if (inName != name()) {
    is.clear(std::ios::badbit | is.rdstate());
    std::cerr << "Mismatch when expecting to read state of a "
              << name() << " distribution\n"
          << "Name found was " << inName
          << "\nistream is left in the badbit state\n";
    return is;
  }
  if (possibleKeywordInput(is, "Uvec", defaultK)) {
    std::vector<unsigned long> t(2);
    is >> defaultK >> t[0] >> t[1]; defaultK = DoubConv::longs2double(t); 
    is >> defaultLambda>>t[0]>>t[1]; defaultLambda = DoubConv::longs2double(t); 
    return is;
  }
  // is >> defaultK encompassed by possibleKeywordInput
  is >> defaultLambda;
  return is;
}

References defaultK, defaultLambda, CLHEP::DoubConv::longs2double(), name(), and CLHEP::possibleKeywordInput().

getTheEngine()

HepRandomEngine * CLHEP::HepRandom::getTheEngine ( )

staticinherited

Definition at line 268 of file Random.cc.

{
  return theDefaults().theEngine.get();
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

Referenced by CLHEP::StaticRandomStates::restore(), CLHEP::RandFlat::restoreEngineStatus(), CLHEP::RandGauss::restoreEngineStatus(), CLHEP::RandFlat::saveEngineStatus(), CLHEP::RandGauss::saveEngineStatus(), CLHEP::RandExponential::shoot(), CLHEP::RandExpZiggurat::shoot(), CLHEP::RandFlat::shoot(), CLHEP::RandGauss::shoot(), CLHEP::RandGaussZiggurat::shoot(), CLHEP::RandChiSquare::shoot(), CLHEP::RandStudentT::shoot(), CLHEP::RandBreitWigner::shoot(), shoot(), CLHEP::RandPoisson::shoot(), CLHEP::RandPoissonQ::shoot(), CLHEP::RandBinomial::shoot(), and CLHEP::RandFlat::shootArray().

getTheGenerator()

HepRandom * CLHEP::HepRandom::getTheGenerator ( )

staticinherited

Definition at line 263 of file Random.cc.

{
  return theDefaults().theGenerator.get();
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theGenerator.

getTheSeed()

long CLHEP::HepRandom::getTheSeed ( )

staticinherited

Definition at line 239 of file Random.cc.

{
  return theDefaults().theEngine->getSeed();
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

getTheSeeds()

const long * CLHEP::HepRandom::getTheSeeds ( )

staticinherited

Definition at line 249 of file Random.cc.

{
  return theDefaults().theEngine->getSeeds();
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

getTheTableSeeds()

void CLHEP::HepRandom::getTheTableSeeds ( long *  seeds, int  index  )

staticinherited

Definition at line 254 of file Random.cc.

{
  if ((index >= 0) && (index < 215)) {
    seeds[0] = seedTable[index][0];
    seeds[1] = seedTable[index][1];
  }
  else seeds = NULL;
}

Referenced by CLHEP::HepJamesRandom::HepJamesRandom(), CLHEP::MTwistEngine::MTwistEngine(), CLHEP::RanecuEngine::RanecuEngine(), CLHEP::Ranlux64Engine::Ranlux64Engine(), CLHEP::RanluxEngine::RanluxEngine(), and CLHEP::RanecuEngine::setSeed().

name()

std::string CLHEP::RandGamma::name ( ) const

virtual

Reimplemented from CLHEP::HepRandom.

Definition at line 27 of file RandGamma.cc.

{return "RandGamma";}

Referenced by source.g4viscp.G4Scene::create_scene(), get(), mcscore.MCParticle::printout(), put(), and source.g4viscp.G4Scene::update_scene().

operator()() [1/2]

double CLHEP::RandGamma::operator() ( )

inlinevirtual

Reimplemented from CLHEP::HepRandom.

operator()() [2/2]

double CLHEP::RandGamma::operator() ( double  k, double  lambda  )

inline

put()

std::ostream & CLHEP::RandGamma::put ( std::ostream &  os ) const

virtual

Reimplemented from CLHEP::HepRandom.

Definition at line 225 of file RandGamma.cc.

                                                    {
  int pr=os.precision(20);
  std::vector<unsigned long> t(2);
  os << " " << name() << "\n";
  os << "Uvec" << "\n";
  t = DoubConv::dto2longs(defaultK);
  os << defaultK << " " << t[0] << " " << t[1] << "\n";
  t = DoubConv::dto2longs(defaultLambda);
  os << defaultLambda << " " << t[0] << " " << t[1] << "\n";
  os.precision(pr);
  return os;
}

References defaultK, defaultLambda, CLHEP::DoubConv::dto2longs(), and name().

restoreDistState()

static std::istream & CLHEP::HepRandom::restoreDistState ( std::istream &  is )

inlinestaticinherited

Definition at line 136 of file Random.h.

{return is;}

restoreEngineStatus()

void CLHEP::HepRandom::restoreEngineStatus ( const char  filename[] = "Config.conf" )

staticinherited

Definition at line 283 of file Random.cc.

{
  theDefaults().theEngine->restoreStatus( filename );
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

restoreFullState()

std::istream & CLHEP::HepRandom::restoreFullState ( std::istream &  is )

staticinherited

Definition at line 293 of file Random.cc.

                                                          {
  is >> *getTheEngine();
  return is;
}

Referenced by CLHEP::RandFlat::restoreFullState(), and CLHEP::RandGauss::restoreFullState().

restoreStaticRandomStates()

std::istream & CLHEP::HepRandom::restoreStaticRandomStates ( std::istream &  is )

staticinherited

Definition at line 302 of file Random.cc.

                                                                   {
  return StaticRandomStates::restore(is);
}

References CLHEP::StaticRandomStates::restore().

saveDistState()

static std::ostream & CLHEP::HepRandom::saveDistState ( std::ostream &  os )

inlinestaticinherited

Definition at line 133 of file Random.h.

{return os;}

saveEngineStatus()

void CLHEP::HepRandom::saveEngineStatus ( const char  filename[] = "Config.conf" )

staticinherited

Definition at line 278 of file Random.cc.

{
  theDefaults().theEngine->saveStatus( filename );
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

Referenced by G4CascadeInterface::ApplyYourself(), G4HadronicProcess::PostStepDoIt(), and G4CascadeInterface::Propagate().

saveFullState()

std::ostream & CLHEP::HepRandom::saveFullState ( std::ostream &  os )

staticinherited

Definition at line 288 of file Random.cc.

                                                       {
  os << *getTheEngine();
  return os;
}

Referenced by G4EventManager::DoProcessing(), G4EventManager::ProcessOneEvent(), CLHEP::RandFlat::saveFullState(), and CLHEP::RandGauss::saveFullState().

saveStaticRandomStates()

std::ostream & CLHEP::HepRandom::saveStaticRandomStates ( std::ostream &  os )

staticinherited

Definition at line 298 of file Random.cc.

                                                                {
  return StaticRandomStates::save(os);
}

References CLHEP::StaticRandomStates::save().

setTheEngine()

void CLHEP::HepRandom::setTheEngine ( HepRandomEngine *  theNewEngine )

staticinherited

Definition at line 273 of file Random.cc.

{
  theDefaults().theEngine.reset( theNewEngine, do_nothing_deleter() );
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

Referenced by CLHEP::StaticRandomStates::restore().

setTheSeed()

void CLHEP::HepRandom::setTheSeed ( long  seed, int  lxr = 3  )

staticinherited

Definition at line 234 of file Random.cc.

{
  theDefaults().theEngine->setSeed(seed,lux);
}

References CLHEP::lux, CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

setTheSeeds()

void CLHEP::HepRandom::setTheSeeds ( const long *  seeds, int  aux = -1  )

staticinherited

Definition at line 244 of file Random.cc.

{
  theDefaults().theEngine->setSeeds(seeds,aux);
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

shoot() [1/4]

static double CLHEP::RandGamma::shoot ( )

inlinestatic

Referenced by shootArray().

shoot() [2/4]

double CLHEP::RandGamma::shoot ( double  k, double  lambda  )

static

Definition at line 38 of file RandGamma.cc.

                                                 {
  HepRandomEngine *anEngine = HepRandom::getTheEngine();
  return genGamma( anEngine, k, lambda );
}

References genGamma(), CLHEP::HepRandom::getTheEngine(), and G4InuclParticleNames::lambda.

shoot() [3/4]

static double CLHEP::RandGamma::shoot ( HepRandomEngine *  anEngine )

inlinestatic

shoot() [4/4]

double CLHEP::RandGamma::shoot ( HepRandomEngine *  anEngine, double  k, double  lambda  )

static

Definition at line 33 of file RandGamma.cc.

                                                                        {
  return genGamma( anEngine, k, lambda );
}

References genGamma(), and G4InuclParticleNames::lambda.

shootArray() [1/2]

void CLHEP::RandGamma::shootArray ( const int  size, double *  vect, double  k = 1.0, double  lambda = 1.0  )

static

Definition at line 47 of file RandGamma.cc.

{
  for( double* v = vect; v != vect + size; ++v )
    *v = shoot(k,lambda);
}

References G4InuclParticleNames::lambda, and shoot().

shootArray() [2/2]

void CLHEP::RandGamma::shootArray ( HepRandomEngine *  anEngine, const int  size, double *  vect, double  k = 1.0, double  lambda = 1.0  )

static

Definition at line 54 of file RandGamma.cc.

{
  for( double* v = vect; v != vect + size; ++v )
    *v = shoot(anEngine,k,lambda);
}

References G4InuclParticleNames::lambda, and shoot().

showEngineStatus()

void CLHEP::HepRandom::showEngineStatus ( )

staticinherited

Definition at line 306 of file Random.cc.

{
  theDefaults().theEngine->showStatus();
}

References CLHEP::anonymous_namespace{Random.cc}::theDefaults(), and CLHEP::anonymous_namespace{Random.cc}::defaults::theEngine.

Field Documentation

defaultK

double CLHEP::RandGamma::defaultK

private

Definition at line 108 of file RandGamma.h.

Referenced by fireArray(), get(), and put().

defaultLambda

double CLHEP::RandGamma::defaultLambda

private

Definition at line 109 of file RandGamma.h.

Referenced by fireArray(), get(), and put().

localEngine

std::shared_ptr<HepRandomEngine> CLHEP::RandGamma::localEngine

private

Definition at line 107 of file RandGamma.h.

Referenced by engine(), and fire().

seedTable

const long CLHEP::HepRandom::seedTable

staticprotectedinherited

Definition at line 156 of file Random.h.

---

The documentation for this class was generated from the following files:

• source/externals/clhep/include/CLHEP/Random/RandGamma.h
• source/externals/clhep/src/RandGamma.cc