ROOT   Reference Guide
TFeldmanCousins Class Reference

Class to calculate the CL upper limit using the Feldman-Cousins method as described in PRD V57 #7, p3873-3889.

The default confidence interval calculated using this method is 90% This is set either by having a default the constructor, or using the appropriate fraction when instantiating an object of this class (e.g. 0.9)

The simple extension to a gaussian resolution function bounded at zero has not been addressed as yet -> ‘time is of the essence’ as they write on the wall of the maze in that classic game ...

#### VARIABLES THAT CAN BE ALTERED

=> depending on your desired precision: The initial values of fMuMin, fMuMax, fMuStep and fNMax are those used in the PRD:

fMuMin = 0.0
fMuMax = 50.0
fMuStep= 0.005

but there is total flexibility in changing this should you desire.

see example of use in \$ROOTSYS/tutorials/math/FeldmanCousins.C

see note about: "Should I use TRolke, TFeldmanCousins, TLimit?" in the TRolke class description.

Definition at line 47 of file TFeldmanCousins.h.

## Public Member Functions

TFeldmanCousins (Double_t newCL=0.9, TString options="")
Constructor. More...

~TFeldmanCousins () override

Double_t CalculateLowerLimit (Double_t Nobserved, Double_t Nbackground)
given Nobserved and Nbackground, try different values of mu that give lower limits that are consistent with Nobserved. More...

Double_t CalculateUpperLimit (Double_t Nobserved, Double_t Nbackground)
given Nobserved and Nbackground, try different values of mu that give upper limits that are consistent with Nobserved. More...

Double_t GetCL (void) const

Double_t GetLowerLimit (void) const

Double_t GetMuMax (void) const

Double_t GetMuMin (void) const

Double_t GetMuStep (void) const

Double_t GetNbackground (void) const

Double_t GetNMax (void) const

Double_t GetNobserved (void) const

Double_t GetUpperLimit (void) const

TClassIsA () const override

void SetCL (Double_t newCL)

void SetMuMax (Double_t newMax=50.0)
Set maximum value of signal to use in calculating the tables. More...

void SetMuMin (Double_t newMin=0.0)

void SetMuStep (Double_t newMuStep=0.005)
Set the step in signal to use when generating tables. More...

void SetNbackground (Double_t Nbg)

void SetNobserved (Double_t NObs)

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

void StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

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

TObject (const TObject &object)
TObject copy ctor. More...

virtual ~TObject ()
TObject destructor. More...

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

Append graphics object to current pad. More...

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

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. More...

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

virtual void Clear (Option_t *="")

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

virtual Int_t Compare (const TObject *obj) const
Compare abstract method. More...

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

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

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

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

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

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

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

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

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. More...

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

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

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

virtual TObjectFindObject (const char *name) const
Must be redefined in derived classes. More...

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

virtual Option_tGetDrawOption () const
Get option used by the graphics system to draw this object. More...

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

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

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

virtual Option_tGetOption () const

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

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

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

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

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. More...

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

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

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

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

void InvertBit (UInt_t f)

virtual TClassIsA () const

Bool_t IsDestructed () const
IsDestructed. More...

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

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

R__ALWAYS_INLINE Bool_t IsOnHeap () const

virtual Bool_t IsSortable () const

R__ALWAYS_INLINE Bool_t IsZombie () const

virtual void ls (Option_t *option="") const
The ls function lists the contents of a class on stdout. More...

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). More...

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

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

void operator delete (void *ptr)
Operator delete. More...

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

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. More...

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

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

virtual void Print (Option_t *option="") const
This method must be overridden when a class wants to print itself. More...

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

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

void ResetBit (UInt_t f)

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

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

void SetBit (UInt_t f)

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

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

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

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

void StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

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

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. More...

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

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

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

## Static Public Member Functions

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. More...

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

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

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

## Protected Member Functions

Int_t FindLimitsFromTable (Double_t mu)
calculate the probability table for a given mu for n = 0, NMAX and return 1 if the number of observed events is consistent with the CL bad More...

Double_t Prob (Int_t N, Double_t mu, Double_t B)
Calculate the poissonian probability for a mean of mu+B events with a variance of N. More...

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). More...

void MakeZombie ()

## Protected Attributes

Double_t fCL

Double_t fLowerLimit

Double_t fMuMax

Double_t fMuMin

Double_t fMuStep

Double_t fNbackground

Int_t fNMax

Int_t fNMuStep

Double_t fNobserved

Int_t fQUICK

Double_t fUpperLimit

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 )) }

#include <TFeldmanCousins.h>

Inheritance diagram for TFeldmanCousins:
[legend]

## ◆ TFeldmanCousins()

 TFeldmanCousins::TFeldmanCousins ( Double_t newCL = 0.9, TString options = "" )

Constructor.

Definition at line 57 of file TFeldmanCousins.cxx.

## ◆ ~TFeldmanCousins()

 TFeldmanCousins::~TFeldmanCousins ( )
override

Definition at line 79 of file TFeldmanCousins.cxx.

## ◆ CalculateLowerLimit()

 Double_t TFeldmanCousins::CalculateLowerLimit ( Double_t Nobserved, Double_t Nbackground )

given Nobserved and Nbackground, try different values of mu that give lower limits that are consistent with Nobserved.

The closed interval (plus any stragglers) corresponds to the F&C interval

Definition at line 88 of file TFeldmanCousins.cxx.

## ◆ CalculateUpperLimit()

 Double_t TFeldmanCousins::CalculateUpperLimit ( Double_t Nobserved, Double_t Nbackground )

given Nobserved and Nbackground, try different values of mu that give upper limits that are consistent with Nobserved.

The closed interval (plus any stragglers) corresponds to the F&C interval

Definition at line 100 of file TFeldmanCousins.cxx.

## ◆ Class()

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

## ◆ Class_Name()

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

## ◆ Class_Version()

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

Definition at line 108 of file TFeldmanCousins.h.

## ◆ DeclFileName()

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

Definition at line 108 of file TFeldmanCousins.h.

## ◆ FindLimitsFromTable()

 Int_t TFeldmanCousins::FindLimitsFromTable ( Double_t mu )
protected

calculate the probability table for a given mu for n = 0, NMAX and return 1 if the number of observed events is consistent with the CL bad

Definition at line 155 of file TFeldmanCousins.cxx.

## ◆ GetCL()

 Double_t TFeldmanCousins::GetCL ( void ) const
inline

Definition at line 93 of file TFeldmanCousins.h.

## ◆ GetLowerLimit()

 Double_t TFeldmanCousins::GetLowerLimit ( void ) const
inline

Definition at line 90 of file TFeldmanCousins.h.

## ◆ GetMuMax()

 Double_t TFeldmanCousins::GetMuMax ( void ) const
inline

Definition at line 96 of file TFeldmanCousins.h.

## ◆ GetMuMin()

 Double_t TFeldmanCousins::GetMuMin ( void ) const
inline

Definition at line 95 of file TFeldmanCousins.h.

## ◆ GetMuStep()

 Double_t TFeldmanCousins::GetMuStep ( void ) const
inline

Definition at line 97 of file TFeldmanCousins.h.

## ◆ GetNbackground()

 Double_t TFeldmanCousins::GetNbackground ( void ) const
inline

Definition at line 92 of file TFeldmanCousins.h.

## ◆ GetNMax()

 Double_t TFeldmanCousins::GetNMax ( void ) const
inline

Definition at line 98 of file TFeldmanCousins.h.

## ◆ GetNobserved()

 Double_t TFeldmanCousins::GetNobserved ( void ) const
inline

Definition at line 91 of file TFeldmanCousins.h.

## ◆ GetUpperLimit()

 Double_t TFeldmanCousins::GetUpperLimit ( void ) const
inline

Definition at line 89 of file TFeldmanCousins.h.

## ◆ IsA()

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

Reimplemented from TObject.

Definition at line 108 of file TFeldmanCousins.h.

## ◆ Prob()

 Double_t TFeldmanCousins::Prob ( Int_t N, Double_t mu, Double_t B )
protected

Calculate the poissonian probability for a mean of mu+B events with a variance of N.

Definition at line 201 of file TFeldmanCousins.cxx.

## ◆ SetCL()

 void TFeldmanCousins::SetCL ( Double_t newCL )
inline

Definition at line 102 of file TFeldmanCousins.h.

## ◆ SetMuMax()

 void TFeldmanCousins::SetMuMax ( Double_t newMax = 50.0 )

Set maximum value of signal to use in calculating the tables.

Definition at line 209 of file TFeldmanCousins.cxx.

## ◆ SetMuMin()

 void TFeldmanCousins::SetMuMin ( Double_t newMin = 0.0 )
inline

Definition at line 104 of file TFeldmanCousins.h.

## ◆ SetMuStep()

 void TFeldmanCousins::SetMuStep ( Double_t newMuStep = 0.005 )

Set the step in signal to use when generating tables.

Definition at line 219 of file TFeldmanCousins.cxx.

## ◆ SetNbackground()

 void TFeldmanCousins::SetNbackground ( Double_t Nbg )
inline

Definition at line 101 of file TFeldmanCousins.h.

## ◆ SetNobserved()

 void TFeldmanCousins::SetNobserved ( Double_t NObs )
inline

Definition at line 100 of file TFeldmanCousins.h.

## ◆ Streamer()

 void TFeldmanCousins::Streamer ( TBuffer & R__b )
overridevirtual

Stream an object of class TObject.

Reimplemented from TObject.

## ◆ StreamerNVirtual()

 void TFeldmanCousins::StreamerNVirtual ( TBuffer & ClassDef_StreamerNVirtual_b )
inline

Definition at line 108 of file TFeldmanCousins.h.

## ◆ fCL

 Double_t TFeldmanCousins::fCL
protected

Definition at line 49 of file TFeldmanCousins.h.

## ◆ fLowerLimit

 Double_t TFeldmanCousins::fLowerLimit
protected

Definition at line 51 of file TFeldmanCousins.h.

## ◆ fMuMax

 Double_t TFeldmanCousins::fMuMax
protected

Definition at line 55 of file TFeldmanCousins.h.

## ◆ fMuMin

 Double_t TFeldmanCousins::fMuMin
protected

Definition at line 54 of file TFeldmanCousins.h.

## ◆ fMuStep

 Double_t TFeldmanCousins::fMuStep
protected

Definition at line 56 of file TFeldmanCousins.h.

## ◆ fNbackground

 Double_t TFeldmanCousins::fNbackground
protected

Definition at line 53 of file TFeldmanCousins.h.

## ◆ fNMax

 Int_t TFeldmanCousins::fNMax
protected

Definition at line 58 of file TFeldmanCousins.h.

## ◆ fNMuStep

 Int_t TFeldmanCousins::fNMuStep
protected

Definition at line 57 of file TFeldmanCousins.h.

## ◆ fNobserved

 Double_t TFeldmanCousins::fNobserved
protected

Definition at line 52 of file TFeldmanCousins.h.

## ◆ fQUICK

 Int_t TFeldmanCousins::fQUICK
protected

Definition at line 59 of file TFeldmanCousins.h.

## ◆ fUpperLimit

 Double_t TFeldmanCousins::fUpperLimit
protected

Definition at line 50 of file TFeldmanCousins.h.

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