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

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

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

virtual	~TRandom1 ()
	destructor

virtual Int_t	GetLuxury () const

virtual UInt_t	GetSeed () const
	Get the random generator seed.

const UInt_t *	GetTheSeeds () const

virtual Double_t	Rndm ()
	Machine independent random number generator.

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

virtual Double_t	Rndm (Int_t)

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

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

virtual void	SetSeed (ULong_t seed)
	Set the state of the generator providing a single seed value and using the luxury level defined when constructing the class The initialisation of the other state values is carried out using a Multiplicative Congruential generator.

virtual void	SetSeed2 (UInt_t seed, Int_t lux=3)
	Set the state of the generator providing a single seed value and a luxury level.

virtual void	SetSeeds (const UInt_t *seeds, Int_t lux=3)
	Set the state of the generator providing an array of seeds The array of seeds can be of size 24 or less.

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

virtual	~TRandom ()
	Default destructor.

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

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

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

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

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.

virtual UInt_t	Integer (UInt_t imax)
	Returns a random integer uniformly distributed on the interval [ 0, imax-1 ].

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.

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

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

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

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

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

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.

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

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

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

Public Member Functions inherited from TNamed
	TNamed ()

	TNamed (const char name, const char title)

	TNamed (const TNamed &named)
	TNamed copy ctor.

	TNamed (const TString &name, const TString &title)

virtual	~TNamed ()
	TNamed destructor.

virtual void	Clear (Option_t *option="")
	Set name and title to empty strings ("").

virtual TObject *	Clone (const char *newname="") const
	Make a clone of an object using the Streamer facility.

virtual Int_t	Compare (const TObject *obj) const
	Compare two TNamed objects.

virtual void	Copy (TObject &named) const
	Copy this to obj.

virtual void	FillBuffer (char *&buffer)
	Encode TNamed into output buffer.

virtual const char *	GetName () const
	Returns name of object.

virtual const char *	GetTitle () const
	Returns title of object.

virtual ULong_t	Hash () const
	Return hash value for this object.

virtual Bool_t	IsSortable () const

virtual void	ls (Option_t *option="") const
	List TNamed name and title.

TNamed &	operator= (const TNamed &rhs)
	TNamed assignment operator.

virtual void	Print (Option_t *option="") const
	Print TNamed name and title.

virtual void	SetName (const char *name)
	Set the name of the TNamed.

virtual void	SetNameTitle (const char name, const char title)
	Set all the TNamed parameters (name and title).

virtual void	SetTitle (const char *title="")
	Set the title of the TNamed.

virtual Int_t	Sizeof () const
	Return size of the TNamed part of the TObject.

Public Member Functions inherited from TObject
	TObject ()
	TObject constructor.

	TObject (const TObject &object)
	TObject copy ctor.

virtual	~TObject ()
	TObject destructor.

void	AbstractMethod (const char *method) const
	Use this method to implement an "abstract" method that you don't want to leave purely abstract.

virtual void	AppendPad (Option_t *option="")
	Append graphics object to current pad.

virtual void	Browse (TBrowser *b)
	Browse object. May be overridden for another default action.

ULong_t	CheckedHash ()
	Check and record whether this class has a consistent Hash/RecursiveRemove setup (*) and then return the regular Hash value for this object.

virtual const char *	ClassName () const
	Returns name of class to which the object belongs.

virtual void	Delete (Option_t *option="")
	Delete this object.

virtual Int_t	DistancetoPrimitive (Int_t px, Int_t py)
	Computes distance from point (px,py) to the object.

virtual void	Draw (Option_t *option="")
	Default Draw method for all objects.

virtual void	DrawClass () const
	Draw class inheritance tree of the class to which this object belongs.

virtual TObject *	DrawClone (Option_t *option="") const
	Draw a clone of this object in the current selected pad for instance with: `gROOT->SetSelectedPad(gPad)`.

virtual void	Dump () const
	Dump contents of object on stdout.

virtual void	Error (const char method, const char msgfmt,...) const
	Issue error message.

virtual void	Execute (const char method, const char params, Int_t *error=0)
	Execute method on this object with the given parameter string, e.g.

virtual void	Execute (TMethod method, TObjArray params, Int_t *error=0)
	Execute method on this object with parameters stored in the TObjArray.

virtual void	ExecuteEvent (Int_t event, Int_t px, Int_t py)
	Execute action corresponding to an event at (px,py).

virtual void	Fatal (const char method, const char msgfmt,...) const
	Issue fatal error message.

virtual TObject *	FindObject (const char *name) const
	Must be redefined in derived classes.

virtual TObject *	FindObject (const TObject *obj) const
	Must be redefined in derived classes.

virtual Option_t *	GetDrawOption () const
	Get option used by the graphics system to draw this object.

virtual const char *	GetIconName () const
	Returns mime type name of object.

virtual char *	GetObjectInfo (Int_t px, Int_t py) const
	Returns string containing info about the object at position (px,py).

virtual Option_t *	GetOption () const

virtual UInt_t	GetUniqueID () const
	Return the unique object id.

virtual Bool_t	HandleTimer (TTimer *timer)
	Execute action in response of a timer timing out.

Bool_t	HasInconsistentHash () const
	Return true is the type of this object is known to have an inconsistent setup for Hash and RecursiveRemove (i.e.

virtual void	Info (const char method, const char msgfmt,...) const
	Issue info message.

virtual Bool_t	InheritsFrom (const char *classname) const
	Returns kTRUE if object inherits from class "classname".

virtual Bool_t	InheritsFrom (const TClass *cl) const
	Returns kTRUE if object inherits from TClass cl.

virtual void	Inspect () const
	Dump contents of this object in a graphics canvas.

void	InvertBit (UInt_t f)

virtual Bool_t	IsEqual (const TObject *obj) const
	Default equal comparison (objects are equal if they have the same address in memory).

virtual Bool_t	IsFolder () const
	Returns kTRUE in case object contains browsable objects (like containers or lists of other objects).

R__ALWAYS_INLINE Bool_t	IsOnHeap () const

R__ALWAYS_INLINE Bool_t	IsZombie () const

void	MayNotUse (const char *method) const
	Use this method to signal that a method (defined in a base class) may not be called in a derived class (in principle against good design since a child class should not provide less functionality than its parent, however, sometimes it is necessary).

virtual Bool_t	Notify ()
	This method must be overridden to handle object notification.

void	Obsolete (const char method, const char asOfVers, const char *removedFromVers) const
	Use this method to declare a method obsolete.

void	operator delete (void *ptr)
	Operator delete.

void	operator delete[] (void *ptr)
	Operator delete [].

void *	operator new (size_t sz)

void *	operator new (size_t sz, void *vp)

void *	operator new[] (size_t sz)

void *	operator new[] (size_t sz, void *vp)

TObject &	operator= (const TObject &rhs)
	TObject assignment operator.

virtual void	Paint (Option_t *option="")
	This method must be overridden if a class wants to paint itself.

virtual void	Pop ()
	Pop on object drawn in a pad to the top of the display list.

virtual Int_t	Read (const char *name)
	Read contents of object with specified name from the current directory.

virtual void	RecursiveRemove (TObject *obj)
	Recursively remove this object from a list.

void	ResetBit (UInt_t f)

virtual void	SaveAs (const char filename="", Option_t option="") const
	Save this object in the file specified by filename.

virtual void	SavePrimitive (std::ostream &out, Option_t *option="")
	Save a primitive as a C++ statement(s) on output stream "out".

void	SetBit (UInt_t f)

void	SetBit (UInt_t f, Bool_t set)
	Set or unset the user status bits as specified in f.

virtual void	SetDrawOption (Option_t *option="")
	Set drawing option for object.

virtual void	SetUniqueID (UInt_t uid)
	Set the unique object id.

virtual void	SysError (const char method, const char msgfmt,...) const
	Issue system error message.

R__ALWAYS_INLINE Bool_t	TestBit (UInt_t f) const

Int_t	TestBits (UInt_t f) const

virtual void	UseCurrentStyle ()
	Set current style settings in this object This function is called when either TCanvas::UseCurrentStyle or TROOT::ForceStyle have been invoked.

virtual void	Warning (const char method, const char msgfmt,...) const
	Issue warning message.

virtual Int_t	Write (const char *name=0, Int_t option=0, Int_t bufsize=0)
	Write this object to the current directory.

virtual Int_t	Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const
	Write this object to the current directory.

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

Static Public Member Functions inherited from TObject
static Long_t	GetDtorOnly ()
	Return destructor only flag.

static Bool_t	GetObjectStat ()
	Get status of object stat flag.

static void	SetDtorOnly (void *obj)
	Set destructor only flag.

static void	SetObjectStat (Bool_t stat)
	Turn on/off tracking of objects in the TObjectTable.

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

Protected Attributes inherited from TNamed
TString	fName

TString	fTitle

Static Protected Attributes
static Int_t	fgMaxIndex = 215

static Int_t	fgNumEngines = 0

Additional Inherited Members
Public Types inherited from TObject
enum	{ kIsOnHeap = 0x01000000 , kNotDeleted = 0x02000000 , kZombie = 0x04000000 , kInconsistent = 0x08000000 , kBitMask = 0x00ffffff }

enum	{ kSingleKey = BIT(0) , kOverwrite = BIT(1) , kWriteDelete = BIT(2) }

enum	EDeprecatedStatusBits { kObjInCanvas = BIT(3) }

enum	EStatusBits { kCanDelete = BIT(0) , kMustCleanup = BIT(3) , kIsReferenced = BIT(4) , kHasUUID = BIT(5) , kCannotPick = BIT(6) , kNoContextMenu = BIT(8) , kInvalidObject = BIT(13) }

Protected Types inherited from TObject
enum	{ kOnlyPrepStep = BIT(3) }

Protected Member Functions inherited from TObject
virtual void	DoError (int level, const char location, const char fmt, va_list va) const
	Interface to ErrorHandler (protected).

void	MakeZombie ()

#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
	)

constructor

Definition at line 314 of file TRandom1.cxx.

◆ ~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

Get the random generator seed.

Note that this function returns the given seed only when using as random generator engine TRandom itself, which is an LCG generator and it has as seed (state) only one 32 bit word. In case of the other generators GetSeed will return one of the state elements and not the given seed. See the documentation of the corresponding generator used (for example TRandom3::GetSeed() when using TRandom3 or gRandom. If one needs to save the generator seed in order to be used later for obtaining reproducible numbers, one should store the full generator, either in a file or in memory in a separate TRandom object. Here is an example on how to store reproducible states:

// set a unique seed
 gRandom->SetSeed(0);
 // save generator state in a different TRandom instance
 TRandom* rngSaved = static_cast<TRandom*>(gRandom->Clone());
 // now both rngSaved and gRandom will produce the same sequence of numbers
 for (int i = 0; i < 10; ++i )
    std::cout << "genrated number from gRandom : " << gRandom->Rndm() << "  from saved generator " <<
    rngSaved->Rndm() << std::endl;

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() [1/3]

Double_t TRandom::Rndm ( )

virtual

Machine independent random number generator.

Based on the BSD Unix (Rand) Linear congrential generator. Produces uniformly-distributed floating points between 0 and 1. Identical sequence on all machines of >= 32 bits. Periodicity = 2**31, generates a number in (0,1). Note that this is a generator which is known to have defects (the lower random bits are correlated) and therefore should NOT be used in any statistical study).

Reimplemented from TRandom.

Definition at line 49 of file TRandom.cxx.

◆ Rndm() [2/3]

Double_t TRandom1::Rndm ( )

virtual

return a random number in ]0,1]

Reimplemented from TRandom.

Definition at line 360 of file TRandom1.cxx.

◆ Rndm() [3/3]

virtual Double_t TRandom::Rndm ( Int_t )

inlinevirtual

Reimplemented from TRandom.

Definition at line 51 of file TRandom.h.

◆ RndmArray() [1/2]

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.

◆ RndmArray() [2/2]

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.

◆ SetSeed()

void TRandom1::SetSeed ( ULong_t seed )

virtual

Set the state of the generator providing a single seed value and using the luxury level defined when constructing the class The initialisation of the other state values is carried out using a Multiplicative Congruential generator.

Note: When seed = 0, a random and unique seed is generated

Parameters

[in] seed seed value (note special case if seed=0)

Reimplemented from TRandom.

Definition at line 598 of file TRandom1.cxx.

◆ SetSeed2()

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

virtual

Set the state of the generator providing a single seed value and a luxury level.

The initialisation of the other state values 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

Note: When the provided seed = 0, a random and unique seed is generated

Parameters

[in]	seed	seed value (note special case if seed=0)
[in]	lux	Luxury level

Definition at line 568 of file TRandom1.cxx.

◆ SetSeeds()

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

virtual

Set the state of the generator providing an array of seeds The array of seeds can be of size 24 or less.

In case of an array of n seeds with n < 24 the n+1 element must be equal to zero. The other elements are the initialized 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

Parameters

[in]	seeds	array of seeds (size from 1 to 24)
[in]	lux	Luxury level

Definition at line 487 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

Additional Inherited Members

Constructor & Destructor Documentation

◆ TRandom1() [1/3]

◆ TRandom1() [2/3]

◆ TRandom1() [3/3]

◆ ~TRandom1()

Member Function Documentation

◆ GetLuxury()

◆ GetSeed()

◆ GetTableSeeds()

◆ GetTheSeeds()

◆ Rndm() [1/3]

◆ Rndm() [2/3]

◆ Rndm() [3/3]

◆ 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