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Reference Guide
TStatistic Class Reference

Statistical variable, defined by its mean and variance (RMS).

Named, streamable, storable and mergeable.

Definition at line 33 of file TStatistic.h.

Public Member Functions

 TStatistic (const char *name, Int_t n, const Double_t *val, const Double_t *w=nullptr)
 Constructor from a vector of values. More...
 
 TStatistic (const char *name="")
 
 ~TStatistic ()
 TStatistic destructor. More...
 
void Fill (Double_t val, Double_t w=1.)
 Increment the entries in the object by one value-weight pair. More...
 
Double_t GetM2 () const
 
Double_t GetMax () const
 
Double_t GetMean () const
 
Double_t GetMeanErr () const
 
Double_t GetMin () const
 
Long64_t GetN () const
 
const char * GetName () const
 Returns name of object. More...
 
Long64_t GetNeff () const
 
Double_t GetRMS () const
 
Double_t GetVar () const
 
Double_t GetW () const
 
Double_t GetW2 () const
 
ULong_t Hash () const
 Return hash value for this object. More...
 
void ls (Option_t *opt="") const
 The ls function lists the contents of a class on stdout. More...
 
Int_t Merge (TCollection *in)
 Merge implementation of TStatistic. More...
 
void Print (Option_t *="") const
 Print the content of the object. More...
 
- 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...
 
virtual void AppendPad (Option_t *option="")
 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=0)
 Execute method on this object with the given parameter string, e.g. More...
 
virtual void Execute (TMethod *method, TObjArray *params, Int_t *error=0)
 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 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...
 
voidoperator new (size_t sz)
 
voidoperator new (size_t sz, void *vp)
 
voidoperator new[] (size_t sz)
 
voidoperator 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 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=0, Int_t option=0, Int_t bufsize=0)
 Write this object to the current directory. More...
 
virtual Int_t Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const
 Write this object to the current directory. More...
 

Private Attributes

Double_t fM
 Sum of elements (i.e. sum of (val * weight) pairs. More...
 
Double_t fM2
 Second order momentum. More...
 
Double_t fMax
 Maximum value in the TStatistic object. More...
 
Double_t fMin
 Minimum value in the TStatistic object. More...
 
Long64_t fN
 Number of fills. More...
 
TString fName
 Name given to the TStatistic object. More...
 
Double_t fW
 Sum of weights. More...
 
Double_t fW2
 Sum of squared weights. More...
 

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)
}
 
- Static Public Member Functions inherited from TObject
static Long_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 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). More...
 
void MakeZombie ()
 

#include <TStatistic.h>

Inheritance diagram for TStatistic:
[legend]

Constructor & Destructor Documentation

◆ TStatistic() [1/2]

TStatistic::TStatistic ( const char *  name = "")
inline

Definition at line 47 of file TStatistic.h.

◆ TStatistic() [2/2]

TStatistic::TStatistic ( const char *  name,
Int_t  n,
const Double_t val,
const Double_t w = nullptr 
)

Constructor from a vector of values.

Parameters
[in]nameThe name given to the object
[in]nThe total number of entries
[in]valThe vector of values
[in]wThe vector of weights for the values

Recursively calls the TStatistic::Fill() function to fill the object.

Definition at line 34 of file TStatistic.cxx.

◆ ~TStatistic()

TStatistic::~TStatistic ( )

TStatistic destructor.

Definition at line 50 of file TStatistic.cxx.

Member Function Documentation

◆ Fill()

void TStatistic::Fill ( Double_t  val,
Double_t  w = 1. 
)

Increment the entries in the object by one value-weight pair.

Parameters
[in]valValue to fill the Tstatistic with
[in]wThe weight of the value

Also updates statistics in the object. For number of entries, sum of weights, sum of squared weights and sum of (value*weight), one extra value is added to the statistic. For the sum of squared (value*weight) pairs, the function uses formula 1.4 in Chan-Golub, LeVeque : Algorithms for computing the Sample Variance (1983), genralized by LM for the case of weights:

\[ \frac{w_j}{\sum_{i=0}^{j} w_i \cdot \sum_{i=0}^{j-1} w_i} \cdot \left( \sum_{i=0}^{j} w_i \cdot val_i - \sum_{i=0}^{j} \left(w_i \cdot val_i\right) \right) \]

The minimum(maximum) is computed by checking that the fill value is either less(greater) than the current minimum(maximum)

Definition at line 76 of file TStatistic.cxx.

◆ GetM2()

Double_t TStatistic::GetM2 ( ) const
inline

Definition at line 57 of file TStatistic.h.

◆ GetMax()

Double_t TStatistic::GetMax ( ) const
inline

Definition at line 65 of file TStatistic.h.

◆ GetMean()

Double_t TStatistic::GetMean ( ) const
inline

Definition at line 58 of file TStatistic.h.

◆ GetMeanErr()

Double_t TStatistic::GetMeanErr ( ) const
inline

Definition at line 59 of file TStatistic.h.

◆ GetMin()

Double_t TStatistic::GetMin ( ) const
inline

Definition at line 64 of file TStatistic.h.

◆ GetN()

Long64_t TStatistic::GetN ( ) const
inline

Definition at line 55 of file TStatistic.h.

◆ GetName()

const char * TStatistic::GetName ( ) const
inlinevirtual

Returns name of object.

This default method returns the class name. Classes that give objects a name should override this method.

Reimplemented from TObject.

Definition at line 52 of file TStatistic.h.

◆ GetNeff()

Long64_t TStatistic::GetNeff ( ) const
inline

Definition at line 56 of file TStatistic.h.

◆ GetRMS()

Double_t TStatistic::GetRMS ( ) const
inline

Definition at line 60 of file TStatistic.h.

◆ GetVar()

Double_t TStatistic::GetVar ( ) const
inline

Definition at line 61 of file TStatistic.h.

◆ GetW()

Double_t TStatistic::GetW ( ) const
inline

Definition at line 62 of file TStatistic.h.

◆ GetW2()

Double_t TStatistic::GetW2 ( ) const
inline

Definition at line 63 of file TStatistic.h.

◆ Hash()

ULong_t TStatistic::Hash ( ) const
inlinevirtual

Return hash value for this object.

Note: If this routine is overloaded in a derived class, this derived class should also add

void CallRecursiveRemoveIfNeeded(TObject &obj)
call RecursiveRemove for obj if gROOT is valid and obj.TestBit(kMustCleanup) is true.
Definition: TROOT.h:395

Otherwise, when RecursiveRemove is called (by ~TObject or example) for this type of object, the transversal of THashList and THashTable containers will will have to be done without call Hash (and hence be linear rather than logarithmic complexity). You will also see warnings like

Error in <ROOT::Internal::TCheckHashRecursiveRemoveConsistency::CheckRecursiveRemove>: The class SomeName overrides TObject::Hash but does not call TROOT::RecursiveRemove in its destructor.
Mother of all ROOT objects.
Definition: TObject.h:37
virtual void Error(const char *method, const char *msgfmt,...) const
Issue error message.
Definition: TObject.cxx:891
void RecursiveRemove(TObject *obj)
Recursively remove this object from the list of Cleanups.
Definition: TROOT.cxx:2429
ULong_t Hash() const
Return hash value for this object.
Definition: TStatistic.h:53

Reimplemented from TObject.

Definition at line 53 of file TStatistic.h.

◆ ls()

void TStatistic::ls ( Option_t option = "") const
inlinevirtual

The ls function lists the contents of a class on stdout.

Ls output is typically much less verbose then Dump().

Reimplemented from TObject.

Definition at line 75 of file TStatistic.h.

◆ Merge()

Int_t TStatistic::Merge ( TCollection in)

Merge implementation of TStatistic.

Parameters
[in]inOther TStatistic objects to be added to the current one

The function merges the statistics of all objects together to form a new one. Merging quantities is done via simple addition for the following class data members:

  • number of entries fN
  • the sum of weights fW
  • the sum of squared weights fW2
  • the sum of (value*weight) fM

The sum of squared (value*weight) pairs fM2 is updated using the same formula as in TStatistic::Fill() function.

The minimum(maximum) is updated by checking that the minimum(maximum) of the next TStatistic object in the queue is either less(greater) than the current minimum(maximum).

Definition at line 135 of file TStatistic.cxx.

◆ Print()

void TStatistic::Print ( Option_t = "") const
virtual

Print the content of the object.

Prints the statistics held by the object in one line. These include the mean, mean error, RMS, the total number of values, the minimum and the maximum.

Reimplemented from TObject.

Definition at line 113 of file TStatistic.cxx.

Member Data Documentation

◆ fM

Double_t TStatistic::fM
private

Sum of elements (i.e. sum of (val * weight) pairs.

Definition at line 40 of file TStatistic.h.

◆ fM2

Double_t TStatistic::fM2
private

Second order momentum.

Definition at line 41 of file TStatistic.h.

◆ fMax

Double_t TStatistic::fMax
private

Maximum value in the TStatistic object.

Definition at line 43 of file TStatistic.h.

◆ fMin

Double_t TStatistic::fMin
private

Minimum value in the TStatistic object.

Definition at line 42 of file TStatistic.h.

◆ fN

Long64_t TStatistic::fN
private

Number of fills.

Definition at line 37 of file TStatistic.h.

◆ fName

TString TStatistic::fName
private

Name given to the TStatistic object.

Definition at line 36 of file TStatistic.h.

◆ fW

Double_t TStatistic::fW
private

Sum of weights.

Definition at line 38 of file TStatistic.h.

◆ fW2

Double_t TStatistic::fW2
private

Sum of squared weights.

Definition at line 39 of file TStatistic.h.

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