ROOT   6.10/09 Reference Guide
THnSparse Class Referenceabstract

Efficient multidimensional histogram.

Use a THnSparse instead of TH1 / TH2 / TH3 / array for histogramming when only a small fraction of bins is filled. A 10-dimensional histogram with 10 bins per dimension has 10^10 bins; in a naive implementation this will not fit in memory. THnSparse only allocates memory for the bins that have non-zero bin content instead, drastically reducing both the memory usage and the access time.

To construct a THnSparse object you must use one of its templated, derived classes:

• THnSparseD (typedef for THnSparseT<ArrayD>): bin content held by a Double_t,
• THnSparseF (typedef for THnSparseT<ArrayF>): bin content held by a Float_t,
• THnSparseL (typedef for THnSparseT<ArrayL>): bin content held by a Long_t,
• THnSparseI (typedef for THnSparseT<ArrayI>): bin content held by an Int_t,
• THnSparseS (typedef for THnSparseT<ArrayS>): bin content held by a Short_t,
• THnSparseC (typedef for THnSparseT<ArrayC>): bin content held by a Char_t,

They take name and title, the number of dimensions, and for each dimension the number of bins, the minimal, and the maximal value on the dimension's axis. A TH2 h("h","h",10, 0., 10., 20, -5., 5.) would correspond to

Int_t bins[2] = {10, 20};
Double_t xmin[2] = {0., -5.};
Double_t xmax[2] = {10., 5.};
THnSparse hs("hs", "hs", 2, bins, min, max);


## Filling

A THnSparse is filled just like a regular histogram, using THnSparse::Fill(x, weight), where x is a n-dimensional Double_t value. To take errors into account, Sumw2() must be called before filling the histogram.

Bins are allocated as needed; the status of the allocation can be observed by GetSparseFractionBins(), GetSparseFractionMem().

## Fast Bin Content Access

When iterating over a THnSparse one should only look at filled bins to save processing time. The number of filled bins is returned by THnSparse::GetNbins(); the bin content for each (linear) bin number can be retrieved by THnSparse::GetBinContent(linidx, (Int_t*)coord). After the call, coord will contain the bin coordinate of each axis for the bin with linear index linidx. A possible call would be

std::cout << hs.GetBinContent(0, coord); std::cout <<" is the content of bin [x = " << coord[0] " << " | y = " << coord[1] << "]" << std::endl;

## Efficiency

TH1 and TH2 are generally faster than THnSparse for one and two dimensional distributions. THnSparse becomes competitive for a sparsely filled TH3 with large numbers of bins per dimension. The tutorial sparsehist.C shows the turning point. On a AMD64 with 8GB memory, THnSparse "wins" starting with a TH3 with 30 bins per dimension. Using a THnSparse for a one-dimensional histogram is only reasonable if it has a huge number of bins.

## Projections

The dimensionality of a THnSparse can be reduced by projecting it to 1, 2, 3, or n dimensions, which can be represented by a TH1, TH2, TH3, or a THnSparse. See the Projection() members. To only project parts of the histogram, call

THnSparse::GetAxis(12)->SetRange(from_bin, to_bin);


## Internal Representation

An entry for a filled bin consists of its n-dimensional coordinates and its bin content. The coordinates are compacted to use as few bits as possible; e.g. a histogram with 10 bins in x and 20 bins in y will only use 4 bits for the x representation and 5 bits for the y representation. This is handled by the internal class THnSparseCompactBinCoord. Bin data (content and coordinates) are allocated in chunks of size fChunkSize; this parameter can be set when constructing a THnSparse. Each chunk is represented by an object of class THnSparseArrayChunk.

Translation from an n-dimensional bin coordinate to the linear index within the chunks is done by GetBin(). It creates a hash from the compacted bin coordinates (the hash of a bin coordinate is the compacted coordinate itself if it takes less than 8 bytes, the size of a Long64_t. This hash is used to lookup the linear index in the TExMap member fBins; the coordinates of the entry fBins points to is compared to the coordinates passed to GetBin(). If they do not match, these two coordinates have the same hash - which is extremely unlikely but (for the case where the compact bin coordinates are larger than 4 bytes) possible. In this case, fBinsContinued contains a chain of linear indexes with the same hash. Iterating through this chain and comparing each bin coordinates with the one passed to GetBin() will retrieve the matching bin.

Definition at line 36 of file THnSparse.h.

## Public Member Functions

virtual ~THnSparse ()
Destruct a THnSparse. More...

void AddBinContent (const Int_t *idx, Double_t v=1.)

void AddBinContent (Long64_t bin, Double_t v=1.)
Add "v" to the content of bin with index "bin". More...

void AddBinError2 (Long64_t bin, Double_t e2)
Add "e" to error of bin with index "bin", enable errors if needed. More...

ROOT::Internal::THnBaseBinIterCreateIter (Bool_t respectAxisRange) const
Create an iterator over all filled bins of a THnSparse. More...

Long64_t GetBin (const Int_t *idx) const

Long64_t GetBin (const Double_t *x) const

Long64_t GetBin (const char *name[]) const

Long64_t GetBin (const Int_t *idx, Bool_t allocate=kTRUE)
Get the bin index for the n dimensional coordinates coord, allocate one if it doesn't exist yet and "allocate" is true. More...

Long64_t GetBin (const Double_t *x, Bool_t allocate=kTRUE)
Get the bin index for the n dimensional tuple x, allocate one if it doesn't exist yet and "allocate" is true. More...

Long64_t GetBin (const char *name[], Bool_t allocate=kTRUE)
Get the bin index for the n dimensional tuple addressed by "name", allocate one if it doesn't exist yet and "allocate" is true. More...

Double_t GetBinContent (const Int_t *idx) const

Double_t GetBinContent (Long64_t bin, Int_t *idx=0) const
Return the content of the filled bin number "idx". More...

Double_t GetBinError2 (Long64_t linidx) const
Get square of the error of bin addressed by linidx as $$\sum weight^{2}$$ If errors are not enabled (via Sumw2() or CalculateErrors()) return contents. More...

Int_t GetChunkSize () const

Long64_t GetNbins () const

Int_t GetNChunks () const

Double_t GetSparseFractionBins () const
Return the amount of filled bins over all bins. More...

Double_t GetSparseFractionMem () const
Return the amount of used memory over memory that would be used by a non-sparse n-dimensional histogram. More...

TH1DProjection (Int_t xDim, Option_t *option="") const

TH2DProjection (Int_t yDim, Int_t xDim, Option_t *option="") const

TH3DProjection (Int_t xDim, Int_t yDim, Int_t zDim, Option_t *option="") const

THnSparseProjection (Int_t ndim, const Int_t *dim, Option_t *option="") const

THnSparseRebin (Int_t group) const

THnSparseRebin (const Int_t *group) const

void Reset (Option_t *option="")
Clear the histogram. More...

void SetBinContent (const Int_t *idx, Double_t v)

void SetBinContent (Long64_t bin, Double_t v)
Set content of bin with index "bin" to "v". More...

void SetBinError2 (Long64_t bin, Double_t e2)
Set error of bin with index "bin" to "e", enable errors if needed. More...

void SetFilledBins (Long64_t nbins)

void Sumw2 ()
Enable calculation of errors. More...

Public Member Functions inherited from THnBase
virtual ~THnBase ()
Destruct a THnBase. More...

void Add (const THnBase *h, Double_t c=1.)
Add contents of h scaled by c to this histogram: this = this + c * h Note that if h has Sumw2 set, Sumw2 is automatically called for this if not already set. More...

void Add (const TH1 *hist, Double_t c=1.)
Fill the THnBase with the bins of hist that have content or error != 0. More...

void AddBinContent (const Int_t *x, Double_t v=1.)

void Browse (TBrowser *b)
Browse a THnSparse: create an entry (ROOT::THnSparseBrowsable) for each dimension. More...

void CalculateErrors (Bool_t calc=kTRUE)

Double_t ComputeIntegral ()
Calculate the integral of the histogram. More...

void Divide (const THnBase *h)
Divide this histogram by h this = this/(h) Note that if h has Sumw2 set, Sumw2 is automatically called for this if not already set. More...

void Divide (const THnBase *h1, const THnBase *h2, Double_t c1=1., Double_t c2=1., Option_t *option="")
Replace contents of this histogram by multiplication of h1 by h2 this = (c1*h1)/(c2*h2) Note that if h1 or h2 have Sumw2 set, Sumw2 is automatically called for this if not already set. More...

Long64_t Fill (const Double_t *x, Double_t w=1.)

Long64_t Fill (const char *name[], Double_t w=1.)

TFitResultPtr Fit (TF1 *f1, Option_t *option="", Option_t *goption="")
Fit a THnSparse with function f. More...

TAxisGetAxis (Int_t dim) const

Double_t GetBinContent (const Int_t *idx) const

Double_t GetBinError (const Int_t *idx) const

Double_t GetBinError (Long64_t linidx) const

Bool_t GetCalculateErrors () const

Double_t GetEntries () const

TObjArrayGetListOfAxes ()

const TObjArrayGetListOfAxes () const

TListGetListOfFunctions ()

Int_t GetNdimensions () const

void GetRandom (Double_t *rand, Bool_t subBinRandom=kTRUE)
Generate an n-dimensional random tuple based on the histogrammed distribution. More...

Double_t GetSumw () const

Double_t GetSumw2 () const

Double_t GetSumwx (Int_t dim) const

Double_t GetSumwx2 (Int_t dim) const

Double_t GetWeightSum () const

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

Bool_t IsInRange (Int_t *coord) const
Check whether bin coord is in range, as defined by TAxis::SetRange(). More...

Long64_t Merge (TCollection *list)
Merge this with a list of THnBase's. More...

void Multiply (const THnBase *h)
Multiply this histogram by histogram h this = this * h Note that if h has Sumw2 set, Sumw2 is automatically called for this if not already set. More...

void Multiply (TF1 *f, Double_t c=1.)
Performs the operation: this = this*c*f1 if errors are defined, errors are also recalculated. More...

void Print (Option_t *option="") const
Print a THnBase. More...

void PrintBin (Int_t *coord, Option_t *options) const

void PrintBin (Long64_t idx, Option_t *options) const
Print bin with linex index "idx". More...

void PrintEntries (Long64_t from=0, Long64_t howmany=-1, Option_t *options=0) const
Print "howmany" entries starting at "from". More...

TH1DProjection (Int_t xDim, Option_t *option="") const

TH2DProjection (Int_t yDim, Int_t xDim, Option_t *option="") const

TH3DProjection (Int_t xDim, Int_t yDim, Int_t zDim, Option_t *option="") const

THnBaseProjectionND (Int_t ndim, const Int_t *dim, Option_t *option="") const

void RebinnedAdd (const THnBase *h, Double_t c=1.)
Add contents of h scaled by c to this histogram: this = this + c * h Note that if h has Sumw2 set, Sumw2 is automatically called for this if not already set. More...

void Scale (Double_t c)
Scale contents and errors of this histogram by c: this = this * c It does not modify the histogram's number of entries. More...

void SetBinContent (const Int_t *idx, Double_t v)

void SetBinEdges (Int_t idim, const Double_t *bins)
Set the axis # of bins and bin limits on dimension idim. More...

void SetBinError (const Int_t *idx, Double_t e)

void SetBinError (Long64_t bin, Double_t e)

void SetEntries (Double_t entries)

void SetTitle (const char *title)
Change (i.e. More...

Public Member Functions inherited from TNamed
TNamed ()

TNamed (const char *name, const char *title)

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

TNamed (const TNamed &named)
TNamed copy ctor. More...

virtual ~TNamed ()

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

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 two TNamed objects. More...

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

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

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

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

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

virtual Bool_t IsSortable () const

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

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

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

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

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

Append graphics object to current pad. More...

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

Bool_t IsOnHeap () const

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

void SetBit (UInt_t f)

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...

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...

## Static Public Member Functions

static THnSparseCreateSparse (const char *name, const char *title, const TH1 *h1, Int_t chunkSize=1024 *16)

static THnSparseCreateSparse (const char *name, const char *title, const THnBase *hn, Int_t chunkSize=1024 *16)

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 Member Functions

THnSparse ()
Construct an empty THnSparse. More...

THnSparse (const char *name, const char *title, Int_t dim, const Int_t *nbins, const Double_t *xmin, const Double_t *xmax, Int_t chunksize)
Construct a THnSparse with "dim" dimensions, with chunksize as the size of the chunks. More...

Create a new chunk of bin content. More...

void FillBin (Long64_t bin, Double_t w)

void FillExMap ()
We have been streamed; set up fBins. More...

virtual TArrayGenerateArray () const =0

Long64_t GetBinIndexForCurrentBin (Bool_t allocate)
Return the index for fCurrentBinIndex. More...

THnSparseArrayChunkGetChunk (Int_t idx) const

THnSparseCompactBinCoord * GetCompactCoord () const
Return THnSparseCompactBinCoord object. More...

void InitStorage (Int_t *nbins, Int_t chunkSize)
Initialize the storage of a histogram created via Init() More...

void Reserve (Long64_t nbins)
Initialize storage for nbins. More...

Protected Member Functions inherited from THnBase
THnBase ()

THnBase (const char *name, const char *title, Int_t dim, const Int_t *nbins, const Double_t *xmin, const Double_t *xmax)
Construct a THnBase with "dim" dimensions, "nbins" holds the number of bins for each dimension; "xmin" and "xmax" the minimal and maximal value for each dimension. More...

void AddInternal (const THnBase *h, Double_t c, Bool_t rebinned)
Add() implementation for both rebinned histograms and those with identical binning. More...

Bool_t CheckConsistency (const THnBase *h, const char *tag) const
Consistency check on (some of) the parameters of two histograms (for operations). More...

THnBaseCloneEmpty (const char *name, const char *title, const TObjArray *axes, Bool_t keepTargetAxis) const
Create a new THnBase object that is of the same type as *this, but with dimensions and bins given by axes. More...

TH1CreateHist (const char *name, const char *title, const TObjArray *axes, Bool_t keepTargetAxis) const
Create an empty histogram with name and title with a given set of axes. More...

void FillBinBase (Double_t w)

void Init (const char *name, const char *title, const TObjArray *axes, Bool_t keepTargetAxis, Int_t chunkSize=1024 *16)
Initialize axes and name. More...

Bool_t PrintBin (Long64_t idx, Int_t *coord, Option_t *options) const
Print one bin. More...

TObjectProjectionAny (Int_t ndim, const Int_t *dim, Bool_t wantNDim, Option_t *option="") const
Project all bins into a ndim-dimensional THn / THnSparse (whatever *this is) or if (ndim < 4 and !wantNDim) a TH1/2/3 histogram, keeping only axes in dim (specifying ndim dimensions). More...

THnBaseRebinBase (Int_t group) const
Combine the content of "group" neighboring bins into a new bin and return the resulting THnBase. More...

THnBaseRebinBase (const Int_t *group) const
Combine the content of "group" neighboring bins for each dimension into a new bin and return the resulting THnBase. More...

void ResetBase (Option_t *option="")
Clear the histogram. More...

void UpdateXStat (const Double_t *x, Double_t w=1.)

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 ()

## Private Member Functions

THnSparse (const THnSparse &)
compact coordinate More...

THnSparseoperator= (const THnSparse &)

## Private Attributes

TObjArray fBinContent

TExMap fBins

TExMap fBinsContinued
filled bins More...

Int_t fChunkSize

THnSparseCompactBinCoord * fCompactCoord
filled bins for non-unique hashes, containing pairs of (bin index 0, bin index 1) More...

Long64_t fFilledBins

Public Types inherited from TObject
enum  { kIsOnHeap = 0x01000000, kNotDeleted = 0x02000000, kZombie = 0x04000000, kBitMask = 0x00ffffff }

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

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

Protected Types inherited from THnBase
enum  { kNoInt, kValidInt, kInvalidInt }
array with bin weight sums More...

Static Protected Member Functions inherited from THnBase
static THnBaseCreateHnAny (const char *name, const char *title, const TH1 *h1, Bool_t sparse, Int_t chunkSize=1024 *16)
Create a THn / THnSparse object from a histogram deriving from TH1. More...

static THnBaseCreateHnAny (const char *name, const char *title, const THnBase *hn, Bool_t sparse, Int_t chunkSize=1024 *16)
Create a THnSparse (if "sparse") or THn from "hn", possibly converting THn <-> THnSparse. More...

Protected Attributes inherited from THnBase
TObjArray fAxes

TObjArray fBrowsables

Double_t fEntries
browser-helpers for each axis More...

Double_tfIntegral

enum THnBase:: { ... }  fIntegralStatus
array with bin weight sums More...

Int_t fNdimensions

Double_t fTsumw

Double_t fTsumw2

TArrayD fTsumwx

TArrayD fTsumwx2

Protected Attributes inherited from TNamed
TString fName

TString fTitle

#include <THnSparse.h>

Inheritance diagram for THnSparse:
[legend]

## ◆ THnSparse() [1/3]

 THnSparse::THnSparse ( const THnSparse & )
private

compact coordinate

## ◆ THnSparse() [2/3]

 THnSparse::THnSparse ( )
protected

Construct an empty THnSparse.

Definition at line 590 of file THnSparse.cxx.

## ◆ THnSparse() [3/3]

 THnSparse::THnSparse ( const char * name, const char * title, Int_t dim, const Int_t * nbins, const Double_t * xmin, const Double_t * xmax, Int_t chunksize )
protected

Construct a THnSparse with "dim" dimensions, with chunksize as the size of the chunks.

"nbins" holds the number of bins for each dimension; "xmin" and "xmax" the minimal and maximal value for each dimension. The arrays "xmin" and "xmax" can be NULL; in that case SetBinEdges() must be called for each dimension.

Definition at line 604 of file THnSparse.cxx.

## ◆ ~THnSparse()

 THnSparse::~THnSparse ( )
virtual

Destruct a THnSparse.

Definition at line 617 of file THnSparse.cxx.

## Member Function Documentation

 void THnSparse::AddBinContent ( const Int_t * idx, Double_t v = 1. )
inline

Definition at line 108 of file THnSparse.h.

 void THnSparse::AddBinContent ( Long64_t bin, Double_t v = 1. )
virtual

Add "v" to the content of bin with index "bin".

Implements THnBase.

Definition at line 624 of file THnSparse.cxx.

 void THnSparse::AddBinError2 ( Long64_t bin, Double_t e2 )
virtual

Add "e" to error of bin with index "bin", enable errors if needed.

Implements THnBase.

Definition at line 932 of file THnSparse.cxx.

protected

Create a new chunk of bin content.

Definition at line 635 of file THnSparse.cxx.

## ◆ CreateIter()

 ROOT::Internal::THnBaseBinIter * THnSparse::CreateIter ( Bool_t respectAxisRange ) const
virtual

Create an iterator over all filled bins of a THnSparse.

Implements THnBase.

Definition at line 897 of file THnSparse.cxx.

## ◆ CreateSparse() [1/2]

 static THnSparse* THnSparse::CreateSparse ( const char * name, const char * title, const TH1 * h1, Int_t chunkSize = 1024 * 16 )
inlinestatic

Definition at line 75 of file THnSparse.h.

## ◆ CreateSparse() [2/2]

 static THnSparse* THnSparse::CreateSparse ( const char * name, const char * title, const THnBase * hn, Int_t chunkSize = 1024 * 16 )
inlinestatic

Definition at line 80 of file THnSparse.h.

## ◆ FillBin()

 void THnSparse::FillBin ( Long64_t bin, Double_t w )
inlineprotectedvirtual

Implements THnBase.

Definition at line 63 of file THnSparse.h.

## ◆ FillExMap()

 void THnSparse::FillExMap ( )
protected

We have been streamed; set up fBins.

Definition at line 656 of file THnSparse.cxx.

## ◆ GenerateArray()

 virtual TArray* THnSparse::GenerateArray ( ) const
protectedpure virtual

Implemented in THnSparseT< CONT >.

## ◆ GetBin() [1/6]

 Long64_t THnSparse::GetBin ( const Int_t * idx ) const
inlinevirtual

Implements THnBase.

Definition at line 94 of file THnSparse.h.

## ◆ GetBin() [2/6]

 Long64_t THnSparse::GetBin ( const Double_t * x ) const
inlinevirtual

Implements THnBase.

Definition at line 95 of file THnSparse.h.

## ◆ GetBin() [3/6]

 Long64_t THnSparse::GetBin ( const char * name[] ) const
inlinevirtual

Implements THnBase.

Definition at line 96 of file THnSparse.h.

## ◆ GetBin() [4/6]

 Long64_t THnSparse::GetBin ( const Int_t * coord, Bool_t allocate = kTRUE )
virtual

Get the bin index for the n dimensional coordinates coord, allocate one if it doesn't exist yet and "allocate" is true.

Implements THnBase.

Definition at line 734 of file THnSparse.cxx.

## ◆ GetBin() [5/6]

 Long64_t THnSparse::GetBin ( const Double_t * x, Bool_t allocate = kTRUE )
virtual

Get the bin index for the n dimensional tuple x, allocate one if it doesn't exist yet and "allocate" is true.

Implements THnBase.

Definition at line 703 of file THnSparse.cxx.

## ◆ GetBin() [6/6]

 Long64_t THnSparse::GetBin ( const char * name[], Bool_t allocate = kTRUE )
virtual

Get the bin index for the n dimensional tuple addressed by "name", allocate one if it doesn't exist yet and "allocate" is true.

Implements THnBase.

Definition at line 719 of file THnSparse.cxx.

## ◆ GetBinContent() [1/2]

 Double_t THnSparse::GetBinContent ( const Int_t * idx ) const
inline

Definition at line 116 of file THnSparse.h.

## ◆ GetBinContent() [2/2]

 Double_t THnSparse::GetBinContent ( Long64_t idx, Int_t * coord = 0 ) const
virtual

Return the content of the filled bin number "idx".

If coord is non-null, it will contain the bin's coordinates for each axis that correspond to the bin.

Implements THnBase.

Definition at line 745 of file THnSparse.cxx.

## ◆ GetBinError2()

 Double_t THnSparse::GetBinError2 ( Long64_t linidx ) const
virtual

Get square of the error of bin addressed by linidx as $$\sum weight^{2}$$ If errors are not enabled (via Sumw2() or CalculateErrors()) return contents.

Implements THnBase.

Definition at line 772 of file THnSparse.cxx.

## ◆ GetBinIndexForCurrentBin()

 Long64_t THnSparse::GetBinIndexForCurrentBin ( Bool_t allocate )
protected

Return the index for fCurrentBinIndex.

If it doesn't exist then return -1, or allocate a new bin if allocate is set

Definition at line 790 of file THnSparse.cxx.

## ◆ GetChunk()

 THnSparseArrayChunk* THnSparse::GetChunk ( Int_t idx ) const
inlineprotected

Definition at line 55 of file THnSparse.h.

## ◆ GetChunkSize()

 Int_t THnSparse::GetChunkSize ( ) const
inline

Definition at line 86 of file THnSparse.h.

## ◆ GetCompactCoord()

 THnSparseCompactBinCoord * THnSparse::GetCompactCoord ( ) const
protected

Return THnSparseCompactBinCoord object.

Definition at line 839 of file THnSparse.cxx.

## ◆ GetNbins()

 Long64_t THnSparse::GetNbins ( ) const
inlinevirtual

Implements THnBase.

Definition at line 91 of file THnSparse.h.

## ◆ GetNChunks()

 Int_t THnSparse::GetNChunks ( ) const
inline

Definition at line 87 of file THnSparse.h.

## ◆ GetSparseFractionBins()

 Double_t THnSparse::GetSparseFractionBins ( ) const

Return the amount of filled bins over all bins.

Definition at line 855 of file THnSparse.cxx.

## ◆ GetSparseFractionMem()

 Double_t THnSparse::GetSparseFractionMem ( ) const

Return the amount of used memory over memory that would be used by a non-sparse n-dimensional histogram.

The value is approximate.

Definition at line 866 of file THnSparse.cxx.

## ◆ InitStorage()

 void THnSparse::InitStorage ( Int_t * nbins, Int_t chunkSize )
protectedvirtual

Initialize the storage of a histogram created via Init()

Implements THnBase.

Definition at line 647 of file THnSparse.cxx.

## ◆ operator=()

 THnSparse& THnSparse::operator= ( const THnSparse & )
private

## ◆ Projection() [1/4]

 TH1D* THnSparse::Projection ( Int_t xDim, Option_t * option = "" ) const
inline

Definition at line 127 of file THnSparse.h.

## ◆ Projection() [2/4]

 TH2D* THnSparse::Projection ( Int_t yDim, Int_t xDim, Option_t * option = "" ) const
inline

Definition at line 134 of file THnSparse.h.

## ◆ Projection() [3/4]

 TH3D* THnSparse::Projection ( Int_t xDim, Int_t yDim, Int_t zDim, Option_t * option = "" ) const
inline

Definition at line 142 of file THnSparse.h.

## ◆ Projection() [4/4]

 THnSparse* THnSparse::Projection ( Int_t ndim, const Int_t * dim, Option_t * option = "" ) const
inline

Definition at line 150 of file THnSparse.h.

## ◆ Rebin() [1/2]

 THnSparse* THnSparse::Rebin ( Int_t group ) const
inline

Definition at line 155 of file THnSparse.h.

## ◆ Rebin() [2/2]

 THnSparse* THnSparse::Rebin ( const Int_t * group ) const
inline

Definition at line 158 of file THnSparse.h.

## ◆ Reserve()

 void THnSparse::Reserve ( Long64_t nbins )
protectedvirtual

Initialize storage for nbins.

Reimplemented from THnBase.

Definition at line 690 of file THnSparse.cxx.

## ◆ Reset()

 void THnSparse::Reset ( Option_t * option = "" )
virtual

Clear the histogram.

Implements THnBase.

Definition at line 963 of file THnSparse.cxx.

## ◆ SetBinContent() [1/2]

 void THnSparse::SetBinContent ( const Int_t * idx, Double_t v )
inline

Definition at line 101 of file THnSparse.h.

## ◆ SetBinContent() [2/2]

 void THnSparse::SetBinContent ( Long64_t bin, Double_t v )
virtual

Set content of bin with index "bin" to "v".

Implements THnBase.

Definition at line 905 of file THnSparse.cxx.

## ◆ SetBinError2()

 void THnSparse::SetBinError2 ( Long64_t bin, Double_t e2 )
virtual

Set error of bin with index "bin" to "e", enable errors if needed.

Implements THnBase.

Definition at line 915 of file THnSparse.cxx.

## ◆ SetFilledBins()

 void THnSparse::SetFilledBins ( Long64_t nbins )
inlinevirtual

Reimplemented from THnBase.

Definition at line 92 of file THnSparse.h.

## ◆ Sumw2()

 void THnSparse::Sumw2 ( )
virtual

Enable calculation of errors.

Implements THnBase.

Definition at line 949 of file THnSparse.cxx.

## ◆ fBinContent

 TObjArray THnSparse::fBinContent
private

Definition at line 40 of file THnSparse.h.

## ◆ fBins

 TExMap THnSparse::fBins
private

Definition at line 41 of file THnSparse.h.

## ◆ fBinsContinued

 TExMap THnSparse::fBinsContinued
private

filled bins

Definition at line 42 of file THnSparse.h.

## ◆ fChunkSize

 Int_t THnSparse::fChunkSize
private

Definition at line 38 of file THnSparse.h.

## ◆ fCompactCoord

 THnSparseCompactBinCoord* THnSparse::fCompactCoord
private

filled bins for non-unique hashes, containing pairs of (bin index 0, bin index 1)

Definition at line 43 of file THnSparse.h.

## ◆ fFilledBins

 Long64_t THnSparse::fFilledBins
private

Definition at line 39 of file THnSparse.h.

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