THStack Class Reference

The Histogram stack class.

A THStack is a collection of TH1 or TH2 histograms. Using THStack::Draw() the histogram collection is drawn in one go according to the drawing option.

THStack::Add() allows to add a new histogram to the list. The THStack does not own the objects in the list.

Stack painting

By default, histograms are shown stacked.

• the first histogram is paint
• then the sum of the first and second, etc

The axis ranges are computed automatically along the X and Y axis in order to show the complete histogram collection.

Stack's drawing options

The specific stack's drawing options are:

• NOSTACK If option "nostack" is specified, histograms are all painted in the same pad as if the option "same" had been specified.
• NOSTACKB If the option "nostackb" is specified histograms are all painted in the same pad next to each other as bar plots.
• PADS if option "pads" is specified, the current pad/canvas is subdivided into a number of pads equal to the number of histograms and each histogram is painted into a separate pad.
• NOCLEAR By default the background of the histograms is erased before drawing the histograms. The option "noclear" avoid this behaviour. This is useful when drawing a THStack on top of an other plot. If the patterns used to draw the histograms in the stack are transparents, then the plot behind will be visible.

See the THistPainter class for the list of valid histograms' painting options.

Example;

{
   THStack *hs = new THStack("hs","");
   TH1F *h1 = new TH1F("h1","test hstack",10,-4,4);
   h1->FillRandom("gaus",20000);
   h1->SetFillColor(kRed);
   hs->Add(h1);
   TH1F *h2 = new TH1F("h2","test hstack",10,-4,4);
   h2->FillRandom("gaus",15000);
   h2->SetFillColor(kBlue);
   hs->Add(h2);
   TH1F *h3 = new TH1F("h3","test hstack",10,-4,4);
   h3->FillRandom("gaus",10000);
   h3->SetFillColor(kGreen);
   hs->Add(h3);
   TCanvas *cs = new TCanvas("cs","cs",10,10,700,900);
   TText T; T.SetTextFont(42); T.SetTextAlign(21);
   cs->Divide(2,2);
   cs->cd(1); hs->Draw(); T.DrawTextNDC(.5,.95,"Default drawing option");
   cs->cd(2); hs->Draw("nostack"); T.DrawTextNDC(.5,.95,"Option \"nostack\"");
   cs->cd(3); hs->Draw("nostackb"); T.DrawTextNDC(.5,.95,"Option \"nostackb\"");
   cs->cd(4); hs->Draw("lego1"); T.DrawTextNDC(.5,.95,"Option \"lego1\"");
   return cs;
}

A more complex example:

 
TCanvas *hstack() {
   THStack *hs = new THStack("hs","Stacked 1D histograms");
   //create three 1-d histograms
   TH1F *h1st = new TH1F("h1st","test hstack",100,-4,4);
   h1st->FillRandom("gaus",20000);
   h1st->SetFillColor(kRed);
   h1st->SetMarkerStyle(21);
   h1st->SetMarkerColor(kRed);
   hs->Add(h1st);
   TH1F *h2st = new TH1F("h2st","test hstack",100,-4,4);
   h2st->FillRandom("gaus",15000);
   h2st->SetFillColor(kBlue);
   h2st->SetMarkerStyle(21);
   h2st->SetMarkerColor(kBlue);
   hs->Add(h2st);
   TH1F *h3st = new TH1F("h3st","test hstack",100,-4,4);
   h3st->FillRandom("gaus",10000);
   h3st->SetFillColor(kGreen);
   h3st->SetMarkerStyle(21);
   h3st->SetMarkerColor(kGreen);
   hs->Add(h3st);
 
   TCanvas *cst = new TCanvas("cst","stacked hists",10,10,700,700);
   cst->Divide(2,2);
   // in top left pad, draw the stack with defaults
   cst->cd(1);
   hs->Draw();
   // in top right pad, draw the stack in non-stack mode
   // and errors option
   cst->cd(2);
   gPad->SetGrid();
   hs->Draw("nostack,e1p");
   //in bottom left, draw in stack mode with "lego1" option
   cst->cd(3);
   gPad->SetFrameFillColor(17);
   gPad->SetTheta(3.77);
   gPad->SetPhi(2.9);
   hs->Draw("lego1");
 
   cst->cd(4);
   //create two 2-D histograms and draw them in stack mode
   gPad->SetFrameFillColor(17);
   THStack *a = new THStack("a","Stacked 2D histograms");
   TF2 *f1 = new TF2("f1",
      "xygaus + xygaus(5) + xylandau(10)",-4,4,-4,4);
   Double_t params1[] = {130,-1.4,1.8,1.5,1, 150,2,0.5,-2,0.5,
      3600,-2,0.7,-3,0.3};
   f1->SetParameters(params1);
   TH2F *h2sta = new TH2F("h2sta","h2sta",20,-4,4,20,-4,4);
   h2sta->SetFillColor(38);
   h2sta->FillRandom("f1",4000);
   TF2 *f2 = new TF2("f2","xygaus + xygaus(5)",-4,4,-4,4);
   Double_t params2[] = {100,-1.4,1.9,1.1,2, 80,2,0.7,-2,0.5};
   f2->SetParameters(params2);
   TH2F *h2stb = new TH2F("h2stb","h2stb",20,-4,4,20,-4,4);
   h2stb->SetFillColor(46);
   h2stb->FillRandom("f2",3000);
   a->Add(h2sta);
   a->Add(h2stb);
   a->Draw();
   return cst;
}

Note that picking is supported for all drawing modes.

Since

ROOT version 6.07/07: Stacks of 2D histograms can also be painted as candle plots:

ROOT version 6.09/02: Stacks of 2D histograms can also be painted as violin plots, combinations of candle and violin plots are possible as well:

 
void candleplotstack()
{
   gStyle->SetTimeOffset(0);
   TRandom *rng       = new TRandom();
   TDatime *dateBegin = new TDatime(2010,1,1,0,0,0);
   TDatime *dateEnd   = new TDatime(2011,1,1,0,0,0);
   int bins = 1000;
   TH2I *h1 = new TH2I("h1","Machine A",6,dateBegin->Convert(),dateEnd->Convert(),bins,0,1000);
   TH2I *h2 = new TH2I("h2","Machine B",6,dateBegin->Convert(),dateEnd->Convert(),bins,0,1000);
   TH2I *hsum = new TH2I("h4","Sum",6,dateBegin->Convert(),dateEnd->Convert(),bins,0,1000);
 
   float Rand;
   for (int i = dateBegin->Convert(); i < dateEnd->Convert(); i+=86400*30) {
      for (int j = 0; j < 1000; j++) {
         Rand = rng->Gaus(500+sin(i/10000000.)*100,50); h1->Fill(i,Rand); hsum->Fill(i,Rand);
         Rand = rng->Gaus(500+sin(i/12000000.)*100,50); h2->Fill(i,Rand); hsum->Fill(i,Rand);
      }
   }
 
   h2->SetLineColor(kRed);
   hsum->SetFillColor(kGreen);
   TCanvas *c1 = new TCanvas();
 
   THStack *hs = new THStack("hs","Machine A+B");
   hs->Add(h1);
   hs->Add(h2,"candle2");
   hs->Add(hsum, "violin1");
   hs->Draw("candle3");
   hs->GetXaxis()->SetNdivisions(410);
   
   gPad->SetGrid(1,0);
 
   hs->GetXaxis()->SetTimeDisplay(1);
   hs->GetXaxis()->SetTimeFormat("%m/%y");
   hs->GetXaxis()->SetTitle("Date [month/year]");
 
   c1->Modified();
 
   gPad->BuildLegend(0.75,0.75,0.95,0.95,"");
}

Automatic coloring according to the current palette is available as shown in the following example:

 
void thstackpalettecolor()
{
   auto hs = new THStack("hs","Stacked 1D histograms colored using kOcean palette");
 
   gStyle->SetPalette(kOcean);
 
   // Create three 1-d histograms  and add them in the stack
   auto h1st = new TH1F("h1st","test hstack",100,-4,4);
   h1st->FillRandom("gaus",20000);
   hs->Add(h1st);
 
   auto h2st = new TH1F("h2st","test hstack",100,-4,4);
   h2st->FillRandom("gaus",15000);
   hs->Add(h2st);
 
   auto h3st = new TH1F("h3st","test hstack",100,-4,4);
   h3st->FillRandom("gaus",10000);
   hs->Add(h3st);
 
   // draw the stack
   hs->Draw("pfc nostack");
}

Definition at line 38 of file THStack.h.

Public Member Functions
	THStack ()
	THStack default constructor.
	THStack (const char *name, const char *title)
	constructor with name and title
	THStack (const THStack &hstack)
	THStack copy constructor.
	THStack (TH1 *hist, Option_t *axis="x", const char *name=0, const char *title=0, Int_t firstbin=1, Int_t lastbin=-1, Int_t firstbin2=1, Int_t lastbin2=-1, Option_t *proj_option="", Option_t *draw_option="")
	Creates a new THStack from a TH2 or TH3 It is filled with the 1D histograms from GetProjectionX or GetProjectionY for each bin of the histogram.
virtual	~THStack ()
	THStack destructor.
virtual void	Add (TH1 *h, Option_t *option="")
	add a new histogram to the list Only 1-d and 2-d histograms currently supported.
TIter	begin () const
	Get iterator over internal hists list.
virtual void	Browse (TBrowser *b)
	Browse.
virtual Int_t	DistancetoPrimitive (Int_t px, Int_t py)
	Compute distance from point px,py to each graph.
virtual void	Draw (Option_t *chopt="")
	Draw this multihist with its current attributes.
TIter	end () const
TH1 *	GetHistogram () const
	Returns a pointer to the histogram used to draw the axis Takes into account the two following cases.
TList *	GetHists () const
virtual Double_t	GetMaximum (Option_t *option="")
	returns the maximum of all added histograms returns the maximum of all histograms if option "nostack".
virtual Double_t	GetMinimum (Option_t *option="")
	returns the minimum of all added histograms returns the minimum of all histograms if option "nostack".
Int_t	GetNhists () const
	Return the number of histograms in the stack.
TObjArray *	GetStack ()
	Return pointer to Stack. Build it if not yet done.
TAxis *	GetXaxis () const
	Get x axis of the histogram used to draw the stack.
TAxis *	GetYaxis () const
	Get y axis of the histogram used to draw the stack.
TAxis *	GetZaxis () const
	Get z axis of the histogram used to draw the stack.
virtual void	ls (Option_t *option="") const
	List histograms in the stack.
virtual Long64_t	Merge (TCollection *li, TFileMergeInfo *info)
	Merge the THStack in the TList into this stack.
virtual void	Modified ()
	invalidate sum of histograms
virtual void	Paint (Option_t *chopt="")
	Paint the list of histograms.
virtual void	Print (Option_t *chopt="") const
	Print the list of histograms.
virtual void	RecursiveRemove (TObject *obj)
	Recursively remove object from the list of histograms.
virtual void	SavePrimitive (std::ostream &out, Option_t *option="")
	Save primitive as a C++ statement(s) on output stream out.
virtual void	SetHistogram (TH1 *h)
virtual void	SetMaximum (Double_t maximum=-1111)
	Set maximum.
virtual void	SetMinimum (Double_t minimum=-1111)
	Set minimum.
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
TNamed &	operator= (const TNamed &rhs)
	TNamed assignment operator.
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.
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 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)
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.
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	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.
void	ResetBit (UInt_t f)
virtual void	SaveAs (const char *filename="", Option_t *option="") const
	Save this object in the file specified by filename.
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.

Protected Member Functions
void	BuildStack ()
	build sum of all histograms Build a separate list fStack containing the running sum of all histograms
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 ()

Protected Attributes
TH1 *	fHistogram
	Pointer to histogram used for drawing axis.
TList *	fHists
	Pointer to array of TH1.
Double_t	fMaximum
	Maximum value for plotting along y.
Double_t	fMinimum
	Minimum value for plotting along y.
TObjArray *	fStack
	! Pointer to array of sums of TH1
Protected Attributes inherited from TNamed
TString	fName
TString	fTitle

Private Member Functions
THStack &	operator= (const THStack &)

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

#include <THStack.h>

Inheritance diagram for THStack:

Constructor & Destructor Documentation

THStack() [1/4]

THStack::THStack

(

)

THStack default constructor.

Definition at line 135 of file THStack.cxx.

THStack() [2/4]

THStack::THStack	(	const char *	name,
		const char *	title
	)

constructor with name and title

Definition at line 147 of file THStack.cxx.

THStack() [3/4]

THStack::THStack	(	TH1 *	hist,
		Option_t *	axis = "x",
		const char *	name = 0,
		const char *	title = 0,
		Int_t	firstbin = 1,
		Int_t	lastbin = -1,
		Int_t	firstbin2 = 1,
		Int_t	lastbin2 = -1,
		Option_t *	proj_option = "",
		Option_t *	draw_option = ""
	)

Creates a new THStack from a TH2 or TH3 It is filled with the 1D histograms from GetProjectionX or GetProjectionY for each bin of the histogram.

It illustrates the differences and total sum along an axis.

Parameters:

• hist: the histogram used for the projections. Can be an object deriving from TH2 or TH3.
• axis: for TH2: "x" for ProjectionX, "y" for ProjectionY. for TH3: see TH3::Project3D.
• name: fName is set to name if given, otherwise to histo's name with "_stack_<axis>" appended, where <axis> is the value of the parameter axis.
• title: fTitle is set to title if given, otherwise to histo's title with ", stack of <axis> projections" appended.
• firstbin, lastbin: for each bin within [firstbin,lastbin] a stack entry is created. See TH2::ProjectionX/Y for use overflow bins. Defaults to "all bins but under- / overflow"
• firstbin2, lastbin2: Other axis range for TH3::Project3D, defaults to "all bins but under- / overflow". Ignored for TH2s
• proj_option: option passed to TH2::ProjectionX/Y and TH3::Project3D (along with axis)
• draw_option: option passed to THStack::Add.

Definition at line 189 of file THStack.cxx.

THStack() [4/4]

THStack::THStack

(

const THStack &

hstack

)

THStack copy constructor.

Definition at line 361 of file THStack.cxx.

~THStack()

THStack::~THStack ( )

virtual

THStack destructor.

Definition at line 342 of file THStack.cxx.

Member Function Documentation

Add()

void THStack::Add ( TH1 *  h1, Option_t *  option = ""  )

virtual

add a new histogram to the list Only 1-d and 2-d histograms currently supported.

A drawing option may be specified

Definition at line 381 of file THStack.cxx.

begin()

TIter THStack::begin

(

)

const

Get iterator over internal hists list.

Definition at line 1102 of file THStack.cxx.

Browse()

void THStack::Browse ( TBrowser *  b )

virtual

Browse.

Reimplemented from TObject.

Definition at line 396 of file THStack.cxx.

BuildStack()

void THStack::BuildStack ( )

protected

build sum of all histograms Build a separate list fStack containing the running sum of all histograms

Definition at line 406 of file THStack.cxx.

DistancetoPrimitive()

Int_t THStack::DistancetoPrimitive ( Int_t  px, Int_t  py  )

virtual

Compute distance from point px,py to each graph.

Reimplemented from TObject.

Definition at line 429 of file THStack.cxx.

Draw()

void THStack::Draw ( Option_t *  option = "" )

virtual

Draw this multihist with its current attributes.

Options to draw histograms are described in THistPainter::Paint By default (if option "nostack" is not specified), histograms will be paint stacked on top of each other.

Reimplemented from TObject.

Definition at line 467 of file THStack.cxx.

end()

TIter THStack::end ( ) const

inline

Definition at line 69 of file THStack.h.

GetHistogram()

TH1 * THStack::GetHistogram

(

)

const

Returns a pointer to the histogram used to draw the axis Takes into account the two following cases.

1- option 'A' was specified in THStack::Draw. Return fHistogram 2- user had called TPad::DrawFrame. return pointer to hframe histogram

IMPORTANT NOTES

• You must call Draw before calling this function. The returned histogram depends on the selected Draw options.
• This function returns a pointer to an intermediate fixed bin size histogram used to set the range and for picking. You cannot use this histogram to return the bin information. You must get a pointer to one of the histograms in the stack, the first one, for example.

Definition at line 498 of file THStack.cxx.

GetHists()

TList * THStack::GetHists ( ) const

inline

Definition at line 67 of file THStack.h.

GetMaximum()

Double_t THStack::GetMaximum ( Option_t *  option = "" )

virtual

returns the maximum of all added histograms returns the maximum of all histograms if option "nostack".

Definition at line 513 of file THStack.cxx.

GetMinimum()

Double_t THStack::GetMinimum ( Option_t *  option = "" )

virtual

returns the minimum of all added histograms returns the minimum of all histograms if option "nostack".

Definition at line 562 of file THStack.cxx.

GetNhists()

Int_t THStack::GetNhists

(

)

const

Return the number of histograms in the stack.

Definition at line 606 of file THStack.cxx.

GetStack()

TObjArray * THStack::GetStack

(

)

Return pointer to Stack. Build it if not yet done.

Definition at line 615 of file THStack.cxx.

GetXaxis()

TAxis * THStack::GetXaxis

(

)

const

Get x axis of the histogram used to draw the stack.

IMPORTANT NOTE You must call Draw before calling this function. The returned histogram depends on the selected Draw options.

Definition at line 628 of file THStack.cxx.

GetYaxis()

TAxis * THStack::GetYaxis

(

)

const

Get y axis of the histogram used to draw the stack.

IMPORTANT NOTE You must call Draw before calling this function. The returned histogram depends on the selected Draw options.

Definition at line 643 of file THStack.cxx.

GetZaxis()

TAxis * THStack::GetZaxis

(

)

const

Get z axis of the histogram used to draw the stack.

IMPORTANT NOTE You must call Draw before calling this function. The returned histogram depends on the selected Draw options.

Definition at line 658 of file THStack.cxx.

ls()

void THStack::ls ( Option_t *  option = "" ) const

virtual

List histograms in the stack.

Reimplemented from TNamed.

Definition at line 670 of file THStack.cxx.

Merge()

Long64_t THStack::Merge ( TCollection *  li, TFileMergeInfo *  info  )

virtual

Merge the THStack in the TList into this stack.

Returns the total number of histograms in the result or -1 in case of an error.

Definition at line 683 of file THStack.cxx.

Modified()

void THStack::Modified ( )

virtual

invalidate sum of histograms

Definition at line 706 of file THStack.cxx.

operator=()

THStack & THStack::operator= ( const THStack &  )

private

Paint()

void THStack::Paint ( Option_t *  chopt = "" )

virtual

Paint the list of histograms.

Reimplemented from TObject.

Definition at line 719 of file THStack.cxx.

Print()

void THStack::Print ( Option_t *  chopt = "" ) const

virtual

Print the list of histograms.

Reimplemented from TNamed.

Definition at line 1007 of file THStack.cxx.

RecursiveRemove()

void THStack::RecursiveRemove ( TObject *  obj )

virtual

Recursively remove object from the list of histograms.

Reimplemented from TObject.

Definition at line 1021 of file THStack.cxx.

SavePrimitive()

void THStack::SavePrimitive ( std::ostream &  out, Option_t *  option = ""  )

virtual

Save primitive as a C++ statement(s) on output stream out.

Reimplemented from TObject.

Definition at line 1031 of file THStack.cxx.

SetHistogram()

virtual void THStack::SetHistogram ( TH1 *  h )

inlinevirtual

Definition at line 84 of file THStack.h.

SetMaximum()

void THStack::SetMaximum ( Double_t  maximum = -1111 )

virtual

Set maximum.

Definition at line 1084 of file THStack.cxx.

SetMinimum()

void THStack::SetMinimum ( Double_t  minimum = -1111 )

virtual

Set minimum.

Definition at line 1093 of file THStack.cxx.

Member Data Documentation

fHistogram

TH1* THStack::fHistogram

protected

Pointer to histogram used for drawing axis.

Definition at line 45 of file THStack.h.

fHists

TList* THStack::fHists

protected

Pointer to array of TH1.

Definition at line 43 of file THStack.h.

fMaximum

Double_t THStack::fMaximum

protected

Maximum value for plotting along y.

Definition at line 46 of file THStack.h.

fMinimum

Double_t THStack::fMinimum

protected

Minimum value for plotting along y.

Definition at line 47 of file THStack.h.

fStack

TObjArray* THStack::fStack

protected

! Pointer to array of sums of TH1

Definition at line 44 of file THStack.h.

Libraries for THStack:

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

• hist/hist/inc/THStack.h
• hist/hist/src/THStack.cxx