The Ranlux Random number generator class.

The algorithm for this random engine has been taken from the original implementation in FORTRAN by Fred James as part of CLHEP.

The initialisation is carried out using a Multiplicative Congruential generator using formula constants of L'Ecuyer as described in "F.James, Comp. Phys. Comm. 60 (1990) 329-344".

Definition at line 27 of file TRandom1.h.

Public Member Functions
	TRandom1 ()
	default constructor More...

	TRandom1 (UInt_t seed, Int_t lux=3)
	Luxury level is set in the same way as the original FORTRAN routine. More...

	TRandom1 (Int_t rowIndex, Int_t colIndex, Int_t lux)

virtual	~TRandom1 ()
	destructor More...

virtual Int_t	GetLuxury () const

virtual UInt_t	GetSeed () const

const UInt_t *	GetTheSeeds () const

virtual Double_t	Rndm ()
	return a random number in ]0,1] More...

virtual void	RndmArray (Int_t size, Float_t *vect)
	return an array of random numbers in ]0,1] More...

virtual void	RndmArray (Int_t size, Double_t *vect)
	return an array of random numbers in ]0,1[ More...

virtual void	SetSeed (ULong_t seed)
	Set the random generator seed. More...

virtual void	SetSeed2 (UInt_t seed, Int_t lux=3)
	The initialisation is carried out using a Multiplicative Congruential generator using formula constants of L'Ecuyer as described in "A review of pseudorandom number generators" (Fred James) published in Computer Physics Communications 60 (1990) pages 329-344. More...

virtual void	SetSeeds (const UInt_t *seeds, Int_t lux=3)
	set seeds More...

Public Member Functions inherited from TRandom
	TRandom (UInt_t seed=65539)
	Default constructor. For seed see SetSeed(). More...

virtual	~TRandom ()
	Default destructor. More...

virtual Int_t	Binomial (Int_t ntot, Double_t prob)
	Generates a random integer N according to the binomial law. More...

virtual Double_t	BreitWigner (Double_t mean=0, Double_t gamma=1)
	Return a number distributed following a BreitWigner function with mean and gamma. More...

virtual void	Circle (Double_t &x, Double_t &y, Double_t r)
	Generates random vectors, uniformly distributed over a circle of given radius. More...

virtual Double_t	Exp (Double_t tau)
	Returns an exponential deviate. More...

virtual Double_t	Gaus (Double_t mean=0, Double_t sigma=1)
	Samples a random number from the standard Normal (Gaussian) Distribution with the given mean and sigma. More...

virtual UInt_t	Integer (UInt_t imax)
	Returns a random integer on [ 0, imax-1 ]. More...

virtual Double_t	Landau (Double_t mean=0, Double_t sigma=1)
	Generate a random number following a Landau distribution with location parameter mu and scale parameter sigma: Landau( (x-mu)/sigma ) Note that mu is not the mpv(most probable value) of the Landa distribution and sigma is not the standard deviation of the distribution which is not defined. More...

virtual Int_t	Poisson (Double_t mean)
	Generates a random integer N according to a Poisson law. More...

virtual Double_t	PoissonD (Double_t mean)
	Generates a random number according to a Poisson law. More...

virtual void	Rannor (Float_t &a, Float_t &b)
	Return 2 numbers distributed following a gaussian with mean=0 and sigma=1. More...

virtual void	Rannor (Double_t &a, Double_t &b)
	Return 2 numbers distributed following a gaussian with mean=0 and sigma=1. More...

virtual void	ReadRandom (const char *filename)
	Reads saved random generator status from filename. More...

virtual Double_t	Rndm (Int_t)

virtual void	Sphere (Double_t &x, Double_t &y, Double_t &z, Double_t r)
	Generates random vectors, uniformly distributed over the surface of a sphere of given radius. More...

virtual Double_t	Uniform (Double_t x1=1)
	Returns a uniform deviate on the interval (0, x1). More...

virtual Double_t	Uniform (Double_t x1, Double_t x2)
	Returns a uniform deviate on the interval (x1, x2). More...

virtual void	WriteRandom (const char *filename) const
	Writes random generator status to filename. More...

Public Member Functions inherited from ROOT::Math::TRandomEngine
virtual	~TRandomEngine ()

Static Public Member Functions
static void	GetTableSeeds (UInt_t *seeds, Int_t index)
	static function returning the table of seeds More...

Protected Attributes
Float_t	fCarry

Int_t	fCount24

Float_t	fFloatSeedTable [24]

Int_t	fIlag

const Int_t	fIntModulus

Int_t	fJlag

Int_t	fLuxury

const Double_t	fMantissaBit12

const Double_t	fMantissaBit24

Int_t	fNskip

const UInt_t *	fTheSeeds

Protected Attributes inherited from TRandom
UInt_t	fSeed

Static Protected Attributes
static Int_t	fgMaxIndex = 215

static Int_t	fgNumEngines = 0

#include <TRandom1.h>

Inheritance diagram for TRandom1:

[legend]

Constructor & Destructor Documentation

◆ TRandom1() [1/3]

TRandom1::TRandom1 ( )

default constructor

Definition at line 287 of file TRandom1.cxx.

◆ TRandom1() [2/3]

TRandom1::TRandom1	(	UInt_t	seed,
		Int_t	lux = `3`
	)

Luxury level is set in the same way as the original FORTRAN routine.

level 0 (p=24): equivalent to the original RCARRY of Marsaglia and Zaman, very long period, but fails many tests. level 1 (p=48): considerable improvement in quality over level 0, now passes the gap test, but still fails spectral test. level 2 (p=97): passes all known tests, but theoretically still defective. level 3 (p=223): DEFAULT VALUE. Any theoretically possible correlations have very small chance of being observed. level 4 (p=389): highest possible luxury, all 24 bits chaotic.

Definition at line 265 of file TRandom1.cxx.

◆ TRandom1() [3/3]

TRandom1::TRandom1	(	Int_t	rowIndex,
		Int_t	colIndex,
		Int_t	lux
	)

◆ ~TRandom1()

TRandom1::~TRandom1 ( )

virtual

destructor

Definition at line 341 of file TRandom1.cxx.

Member Function Documentation

◆ GetLuxury()

virtual Int_t TRandom1::GetLuxury ( ) const

inlinevirtual

Definition at line 49 of file TRandom1.h.

◆ GetSeed()

virtual UInt_t TRandom1::GetSeed ( ) const

inlinevirtual

Reimplemented from TRandom.

Definition at line 51 of file TRandom1.h.

◆ GetTableSeeds()

void TRandom1::GetTableSeeds	(	UInt_t *	seeds,
		Int_t	index
	)

static

static function returning the table of seeds

Definition at line 348 of file TRandom1.cxx.

◆ GetTheSeeds()

const UInt_t* TRandom1::GetTheSeeds ( ) const

inline

Definition at line 53 of file TRandom1.h.

◆ Rndm()

Double_t TRandom1::Rndm ( )

virtual

return a random number in ]0,1]

Reimplemented from TRandom.

Definition at line 360 of file TRandom1.cxx.

◆ RndmArray() [1/2]

void TRandom1::RndmArray	(	Int_t	size,
		Float_t *	vect
	)

virtual

return an array of random numbers in ]0,1]

Reimplemented from TRandom.

Definition at line 413 of file TRandom1.cxx.

◆ RndmArray() [2/2]

void TRandom1::RndmArray	(	Int_t	size,
		Double_t *	vect
	)

virtual

return an array of random numbers in ]0,1[

Reimplemented from TRandom.

Definition at line 421 of file TRandom1.cxx.

◆ SetSeed()

void TRandom1::SetSeed ( ULong_t seed )

virtual

Set the random generator seed.

Note that default value is zero, which is different than the default value used when constructing the class. If the seed is zero the seed is set to a random value which in case of TRandom depends on the lowest 4 bytes of TUUID The UUID will be identical if SetSeed(0) is called with time smaller than 100 ns Instead if a different generator implementation is used (TRandom1, 2 or 3) the seed is generated using a 128 bit UUID. This results in different seeds and then random sequence for every SetSeed(0) call.

Reimplemented from TRandom.

Definition at line 619 of file TRandom1.cxx.

◆ SetSeed2()

void TRandom1::SetSeed2	(	UInt_t	seed,
		Int_t	lux = `3`
	)

virtual

The initialisation is carried out using a Multiplicative Congruential generator using formula constants of L'Ecuyer as described in "A review of pseudorandom number generators" (Fred James) published in Computer Physics Communications 60 (1990) pages 329-344.

modified for the case of seed = 0. In that case a random 64 bits seed based on TUUID (using TRandom3(0) ) is generated in order to have a unique seed

Definition at line 555 of file TRandom1.cxx.

◆ SetSeeds()

void TRandom1::SetSeeds	(	const UInt_t *	seeds,
		Int_t	lux = `3`
	)

virtual

set seeds

Definition at line 478 of file TRandom1.cxx.

Member Data Documentation

◆ fCarry

Float_t TRandom1::fCarry

protected

Definition at line 36 of file TRandom1.h.

◆ fCount24

Int_t TRandom1::fCount24

protected

Definition at line 34 of file TRandom1.h.

◆ fFloatSeedTable

Float_t TRandom1::fFloatSeedTable[24]

protected

Definition at line 35 of file TRandom1.h.

◆ fgMaxIndex

int TRandom1::fgMaxIndex = 215

staticprotected

Definition at line 39 of file TRandom1.h.

◆ fgNumEngines

int TRandom1::fgNumEngines = 0

staticprotected

Definition at line 38 of file TRandom1.h.

◆ fIlag

Int_t TRandom1::fIlag

protected

Definition at line 32 of file TRandom1.h.

◆ fIntModulus

const Int_t TRandom1::fIntModulus

protected

Definition at line 37 of file TRandom1.h.

◆ fJlag

Int_t TRandom1::fJlag

protected

Definition at line 33 of file TRandom1.h.

◆ fLuxury

Int_t TRandom1::fLuxury

protected

Definition at line 31 of file TRandom1.h.

◆ fMantissaBit12

const Double_t TRandom1::fMantissaBit12

protected

Definition at line 42 of file TRandom1.h.

◆ fMantissaBit24

const Double_t TRandom1::fMantissaBit24

protected

Definition at line 41 of file TRandom1.h.

◆ fNskip

Int_t TRandom1::fNskip

protected

Definition at line 30 of file TRandom1.h.

◆ fTheSeeds

const UInt_t* TRandom1::fTheSeeds

protected

Definition at line 40 of file TRandom1.h.

Libraries for TRandom1:

[legend]

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

math/mathcore/inc/TRandom1.h
math/mathcore/src/TRandom1.cxx

Public Member Functions

Static Public Member Functions

Protected Attributes

Static Protected Attributes

Constructor & Destructor Documentation

◆ TRandom1() [1/3]

◆ TRandom1() [2/3]

◆ TRandom1() [3/3]

◆ ~TRandom1()

Member Function Documentation

◆ GetLuxury()

◆ GetSeed()

◆ GetTableSeeds()

◆ GetTheSeeds()

◆ Rndm()

◆ RndmArray() [1/2]

◆ RndmArray() [2/2]

◆ SetSeed()

◆ SetSeed2()

◆ SetSeeds()

Member Data Documentation

◆ fCarry

◆ fCount24

◆ fFloatSeedTable

◆ fgMaxIndex

◆ fgNumEngines

◆ fIlag

◆ fIntModulus

◆ fJlag

◆ fLuxury

◆ fMantissaBit12

◆ fMantissaBit24

◆ fNskip

◆ fTheSeeds