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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.

~TRandom1 () override
Destructor.

virtual Int_t GetLuxury () const
Returns current luxury value.

UInt_t GetSeed () const override
Returns the current seed (first element of the seed table)

const UInt_tGetTheSeeds () const
Returns the pointer to the current seeds array.

TClassIsA () const override

Double_t Rndm () override
Machine independent random number generator.

Double_t Rndm () override
Returns a random number in ]0,1].

virtual Double_t Rndm (Int_t)

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

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

void SetSeed (ULong_t seed) override
Set the state of the generator providing a single seed value and using the luxury level defined when constructing the class.

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.

void Streamer (TBuffer &) override
Stream an object of class TObject.

void StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

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

~TRandom () override
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 ULong64_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.

void StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

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.

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

TObjectClone (const char *newname="") const override
Make a clone of an object using the Streamer facility.

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

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

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

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

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

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

Bool_t IsSortable () const override

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

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

void Print (Option_t *option="") const override
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.

void StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

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.

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 TObjectDrawClone (Option_t *option="") const
Draw a clone of this object in the current selected pad with: gROOT->SetSelectedPad(c1).

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=nullptr)
Execute method on this object with the given parameter string, e.g.

virtual void Execute (TMethod *method, TObjArray *params, Int_t *error=nullptr)
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 TObjectFindObject (const char *name) const
Must be redefined in derived classes.

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

virtual Option_tGetDrawOption () 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_tGetOption () 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)

Bool_t IsDestructed () const
IsDestructed.

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 (the base implementation is no-op).

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, void *vp)
Only called by placement new when throwing an exception.

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

void operator delete[] (void *ptr, void *vp)
Only called by placement new[] when throwing an exception.

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)

TObjectoperator= (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.

void StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

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=nullptr, Int_t option=0, Int_t bufsize=0)
Write this object to the current directory.

virtual Int_t Write (const char *name=nullptr, 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 TClassClass ()

static const char * Class_Name ()

static constexpr Version_t Class_Version ()

static const char * DeclFileName ()

static void GetTableSeeds (UInt_t *seeds, Int_t index)
Returns an array of seed values stored in the table, given the index.

Static Public Member Functions inherited from TRandom
static TClassClass ()

static const char * Class_Name ()

static constexpr Version_t Class_Version ()

static const char * DeclFileName ()

Static Public Member Functions inherited from TNamed
static TClassClass ()

static const char * Class_Name ()

static constexpr Version_t Class_Version ()

static const char * DeclFileName ()

Static Public Member Functions inherited from TObject
static TClassClass ()

static const char * Class_Name ()

static constexpr Version_t Class_Version ()

static const char * DeclFileName ()

static Longptr_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
Temporary array of seed values (transient)

Int_t fNskip

const UInt_tfTheSeeds

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

Public Types inherited from TObject
enum  {
kIsOnHeap = 0x01000000 , kNotDeleted = 0x02000000 , kZombie = 0x04000000 , kInconsistent = 0x08000000 ,
}

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

enum  EDeprecatedStatusBits { kObjInCanvas = (1ULL << ( 3 )) }

enum  EStatusBits {
kCanDelete = (1ULL << ( 0 )) , kMustCleanup = (1ULL << ( 3 )) , kIsReferenced = (1ULL << ( 4 )) , kHasUUID = (1ULL << ( 5 )) ,
kCannotPick = (1ULL << ( 6 )) , kNoContextMenu = (1ULL << ( 8 )) , kInvalidObject = (1ULL << ( 13 ))
}

Protected Types inherited from TObject
enum  { kOnlyPrepStep = (1ULL << ( 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]

## ◆ TRandom1() [1/3]

 TRandom1::TRandom1 ( )

Default constructor.

Definition at line 284 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 263 of file TRandom1.cxx.

## ◆ TRandom1() [3/3]

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

Constructor.

Definition at line 310 of file TRandom1.cxx.

## ◆ ~TRandom1()

 TRandom1::~TRandom1 ( )
override

Destructor.

Definition at line 336 of file TRandom1.cxx.

## ◆ Class()

 static TClass * TRandom1::Class ( )
static
Returns
TClass describing this class

## ◆ Class_Name()

 static const char * TRandom1::Class_Name ( )
static
Returns
Name of this class

## ◆ Class_Version()

 static constexpr Version_t TRandom1::Class_Version ( )
inlinestaticconstexpr
Returns
Version of this class

Definition at line 73 of file TRandom1.h.

## ◆ DeclFileName()

 static const char * TRandom1::DeclFileName ( )
inlinestatic
Returns
Name of the file containing the class declaration

Definition at line 73 of file TRandom1.h.

## ◆ GetLuxury()

 virtual Int_t TRandom1::GetLuxury ( ) const
inlinevirtual

Returns current luxury value.

Definition at line 51 of file TRandom1.h.

## ◆ GetSeed()

 UInt_t TRandom1::GetSeed ( ) const
inlineoverridevirtual

Returns the current seed (first element of the seed table)

Warning
This is not the initial seed!

Reimplemented from TRandom.

Definition at line 55 of file TRandom1.h.

## ◆ GetTableSeeds()

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

Returns an array of seed values stored in the table, given the index.

Static function returning the seeds table.

Definition at line 342 of file TRandom1.cxx.

## ◆ GetTheSeeds()

 const UInt_t * TRandom1::GetTheSeeds ( ) const
inline

Returns the pointer to the current seeds array.

Definition at line 58 of file TRandom1.h.

## ◆ IsA()

 TClass * TRandom1::IsA ( ) const
inlineoverridevirtual
Returns
TClass describing current object

Reimplemented from TRandom.

Definition at line 73 of file TRandom1.h.

## ◆ Rndm() [1/3]

 Double_t TRandom::Rndm ( )
overridevirtual

Machine independent random number generator.

Based on the BSD Unix (Rand) Linear congruential 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 ( )
overridevirtual

Returns a random number in ]0,1].

Reimplemented from TRandom.

Definition at line 353 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 )
overridevirtual

Returns an array of random numbers in ]0,1[.

Reimplemented from TRandom.

Definition at line 412 of file TRandom1.cxx.

## ◆ RndmArray() [2/2]

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

Returns an array of random numbers in ]0,1].

Reimplemented from TRandom.

Definition at line 405 of file TRandom1.cxx.

## ◆ SetSeed()

 void TRandom1::SetSeed ( ULong_t seed )
overridevirtual

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 593 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 provided with 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 561 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 479 of file TRandom1.cxx.

## ◆ Streamer()

 void TRandom1::Streamer ( TBuffer & R__b )
overridevirtual

Stream an object of class TObject.

Reimplemented from TRandom.

## ◆ StreamerNVirtual()

 void TRandom1::StreamerNVirtual ( TBuffer & ClassDef_StreamerNVirtual_b )
inline

Definition at line 73 of file TRandom1.h.

## ◆ 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

Temporary array of seed values (transient)

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:

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