Class to compute nice axis limits.

This class is called by default by the histogramming system and also by TTree::Draw, TTreePlayer::DrawSelect. TGaxis use it also to optimize axis labels.

A different finder may be specified via THLimitsFinder::SetFinder.

Definition at line 28 of file THLimitsFinder.h.

Public Member Functions
	THLimitsFinder ()

	~THLimitsFinder () override

virtual Int_t	FindGoodLimits (TH1 *h, Double_t xmin, Double_t xmax)
	Compute the best axis limits for the X axis.

virtual Int_t	FindGoodLimits (TH1 *h, Double_t xmin, Double_t xmax, Double_t ymin, Double_t ymax)
	Compute the best axis limits for the X and Y axis.

virtual Int_t	FindGoodLimits (TH1 *h, Double_t xmin, Double_t xmax, Double_t ymin, Double_t ymax, Double_t zmin, Double_t zmax)
	Compute the best axis limits for the X, Y and Z axis.

TClass *	IsA () const override

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

void	StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

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

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

virtual	~TObject ()
	TObject destructor.

void	AbstractMethod (const char *method) const
	Call this function within a function that you don't want to define as purely virtual, in order not to force all users deriving from that class to implement that maybe (on their side) unused function; but at the same time, emit a run-time warning if they try to call it, telling that it is not implemented in the derived class: action must thus be taken on the user side to override it.

virtual void	AppendPad (Option_t *option="")
	Append graphics object to current pad.

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

ULong_t	CheckedHash ()
	Check and record whether this class has a consistent Hash/RecursiveRemove setup (*) and then return the regular Hash value for this object.

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

virtual void	Clear (Option_t *="")

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 abstract method.

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

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

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

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

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

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

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

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

virtual void	Execute (const char method, const char params, Int_t *error=nullptr)
	Execute method on this object with the given parameter string, e.g.

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

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

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

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

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.

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

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

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.

void	MayNotUse (const char *method) const
	Use this method to signal that a method (defined in a base class) may not be called in a derived class (in principle against good design since a child class should not provide less functionality than its parent, however, sometimes it is necessary).

virtual Bool_t	Notify ()
	This method must be overridden to handle object notification (the base implementation is no-op).

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

void	operator delete (void *, size_t)
	Operator delete for sized deallocation.

void	operator delete (void *ptr)
	Operator delete.

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

void	operator delete[] (void *, size_t)
	Operator delete [] for sized deallocation.

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

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

void *	operator new (size_t sz)

void *	operator new (size_t sz, void *vp)

void *	operator new[] (size_t sz)

void *	operator new[] (size_t sz, void *vp)

TObject &	operator= (const TObject &rhs) noexcept
	TObject assignment operator.

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

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

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

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

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

void	ResetBit (UInt_t f)

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

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

void	SetBit (UInt_t f)

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

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

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

void	StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

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

R__ALWAYS_INLINE Bool_t	TestBit (UInt_t f) const

Int_t	TestBits (UInt_t f) const

virtual void	UseCurrentStyle ()
	Set current style settings in this object This function is called when either TCanvas::UseCurrentStyle or TROOT::ForceStyle have been invoked.

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

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

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

Static Public Member Functions
static TClass *	Class ()

static const char *	Class_Name ()

static constexpr Version_t	Class_Version ()

static const char *	DeclFileName ()

static THLimitsFinder *	GetLimitsFinder ()
	Return pointer to the current finder.

static void	Optimize (Double_t A1, Double_t A2, Int_t nold, Double_t &BinLow, Double_t &BinHigh, Int_t &nbins, Double_t &BWID, Option_t *option="")
	Static function to compute reasonable axis limits.

static void	OptimizeLimits (Int_t nbins, Int_t &newbins, Double_t &xmin, Double_t &xmax, Bool_t isInteger)
	Optimize axis limits.

static void	SetLimitsFinder (THLimitsFinder *finder)
	This static function can be used to specify a finder derived from THLimitsFinder.

Static Public Member Functions inherited from TObject
static TClass *	Class ()

static const char *	Class_Name ()

static constexpr Version_t	Class_Version ()

static const char *	DeclFileName ()

static Longptr_t	GetDtorOnly ()
	Return destructor only flag.

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

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

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

Static Protected Attributes
static THLimitsFinder *	fgLimitsFinder = nullptr
	! Pointer to hist limits finder

Additional Inherited Members
Public Types inherited from TObject
enum	{ kIsOnHeap = 0x01000000 , kNotDeleted = 0x02000000 , kZombie = 0x04000000 , kInconsistent = 0x08000000 , kBitMask = 0x00ffffff }

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

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

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

Protected Types inherited from TObject
enum	{ kOnlyPrepStep = (1ULL << ( 3 )) }

Protected Member Functions inherited from TObject
virtual void	DoError (int level, const char location, const char fmt, va_list va) const
	Interface to ErrorHandler (protected).

void	MakeZombie ()

Static Protected Member Functions inherited from TObject
static void	SavePrimitiveConstructor (std::ostream &out, TClass cl, const char variable_name, const char *constructor_agrs="", Bool_t empty_line=kTRUE)
	Save object constructor in the output stream "out".

static void	SavePrimitiveDraw (std::ostream &out, const char variable_name, Option_t option=nullptr)
	Save invocation of primitive Draw() method Skipped if option contains "nodraw" string.

static TString	SavePrimitiveVector (std::ostream &out, const char prefix, Int_t len, Double_t arr, Bool_t empty_line=kFALSE)
	Save array in the output stream "out" as vector.

#include <THLimitsFinder.h>

Inheritance diagram for THLimitsFinder:

[legend]

Constructor & Destructor Documentation

◆ THLimitsFinder()

THLimitsFinder::THLimitsFinder ( )

Definition at line 31 of file THLimitsFinder.cxx.

◆ ~THLimitsFinder()

THLimitsFinder::~THLimitsFinder ( )

override

Definition at line 37 of file THLimitsFinder.cxx.

Member Function Documentation

◆ Class()

static TClass * THLimitsFinder::Class ( )

static

Returns: TClass describing this class

◆ Class_Name()

static const char * THLimitsFinder::Class_Name ( )

static

Returns: Name of this class

◆ Class_Version()

static constexpr Version_t THLimitsFinder::Class_Version ( )

inlinestaticconstexpr

Returns: Version of this class

Definition at line 46 of file THLimitsFinder.h.

◆ DeclFileName()

static const char * THLimitsFinder::DeclFileName ( )

inlinestatic

Returns: Name of the file containing the class declaration

Definition at line 46 of file THLimitsFinder.h.

◆ FindGoodLimits() [1/3]

Int_t THLimitsFinder::FindGoodLimits	(	TH1 *	h,
		Double_t	xmin,
		Double_t	xmax )

virtual

Compute the best axis limits for the X axis.

If the bit kIsInteger is set, the number of channels is also recomputed. The axis parameters are replaced by the optimized parameters.

Example: With the input parameters xmin=-1.467 and xmax=2.344, the function will compute better limits -1.8 and 2.7 and store them in the axis.

Definition at line 52 of file THLimitsFinder.cxx.

◆ FindGoodLimits() [2/3]

Int_t THLimitsFinder::FindGoodLimits	(	TH1 *	h,
		Double_t	xmin,
		Double_t	xmax,
		Double_t	ymin,
		Double_t	ymax )

virtual

Compute the best axis limits for the X and Y axis.

If the bit kIsInteger is set, the number of channels is also recomputed. The axis parameters are replaced by the optimized parameters

Definition at line 77 of file THLimitsFinder.cxx.

◆ FindGoodLimits() [3/3]

Int_t THLimitsFinder::FindGoodLimits	(	TH1 *	h,
		Double_t	xmin,
		Double_t	xmax,
		Double_t	ymin,
		Double_t	ymax,
		Double_t	zmin,
		Double_t	zmax )

virtual

Compute the best axis limits for the X, Y and Z axis.

If the bit kIsInteger is set, the number of channels is also recomputed. The axis parameters are replaced by the optimized parameters

Definition at line 110 of file THLimitsFinder.cxx.

◆ GetLimitsFinder()

THLimitsFinder * THLimitsFinder::GetLimitsFinder ( )

static

Return pointer to the current finder.

Create one if none exists Use SetLimitsFinder to set a user defined finder.

Definition at line 152 of file THLimitsFinder.cxx.

◆ IsA()

TClass * THLimitsFinder::IsA ( ) const

inlineoverridevirtual

Returns: TClass describing current object

Reimplemented from TObject.

Definition at line 46 of file THLimitsFinder.h.

◆ Optimize()

void THLimitsFinder::Optimize	(	Double_t	A1,
		Double_t	A2,
		Int_t	nold,
		Double_t &	BinLow,
		Double_t &	BinHigh,
		Int_t &	nbins,
		Double_t &	BinWidth,
		Option_t *	option = "" )

static

Static function to compute reasonable axis limits.

Input parameters:

Parameters

[in]	A1,A2	: Original axis limits
[in]	BinLow,BinHigh	: Optimized axis limits. They should be initialized by the calling method for instance to 0.
[out]	nold	: Original number of divisions.
[out]	nbins	: Optimized number of divisions.
[out]	BinWidth	: Optimized bin width. It should be initialized by the calling method for instance to 0.
[in]	option	: "T" means Time axis.

Definition at line 183 of file THLimitsFinder.cxx.

◆ OptimizeLimits()

void THLimitsFinder::OptimizeLimits	(	Int_t	nbins,
		Int_t &	newbins,
		Double_t &	xmin,
		Double_t &	xmax,
		Bool_t	isInteger )

static

Optimize axis limits.

When isInter=kTRUE, the function makes an integer binwidth and recompute the number of bins accordingly.

Definition at line 366 of file THLimitsFinder.cxx.

◆ SetLimitsFinder()

void THLimitsFinder::SetLimitsFinder ( THLimitsFinder * finder )

static

This static function can be used to specify a finder derived from THLimitsFinder.

The finder may redefine the functions FindGoodLimits. Note that the redefined functions may call THLimitsFinder::FindGoodLimits.

Definition at line 164 of file THLimitsFinder.cxx.

◆ Streamer()

void THLimitsFinder::Streamer ( TBuffer & R__b )

overridevirtual

Stream an object of class TObject.

Reimplemented from TObject.

◆ StreamerNVirtual()

void THLimitsFinder::StreamerNVirtual ( TBuffer & ClassDef_StreamerNVirtual_b )

inline

Definition at line 46 of file THLimitsFinder.h.

Member Data Documentation

◆ fgLimitsFinder

THLimitsFinder * THLimitsFinder::fgLimitsFinder = nullptr

staticprotected

! Pointer to hist limits finder

Definition at line 31 of file THLimitsFinder.h.

Libraries for THLimitsFinder:

[legend]

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

hist/hist/inc/THLimitsFinder.h
hist/hist/src/THLimitsFinder.cxx

Public Member Functions

Static Public Member Functions

Static Protected Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ THLimitsFinder()

◆ ~THLimitsFinder()

Member Function Documentation

◆ Class()

◆ Class_Name()

◆ Class_Version()

◆ DeclFileName()

◆ FindGoodLimits() [1/3]

◆ FindGoodLimits() [2/3]

◆ FindGoodLimits() [3/3]

◆ GetLimitsFinder()

◆ IsA()

◆ Optimize()

◆ OptimizeLimits()

◆ SetLimitsFinder()

◆ Streamer()

◆ StreamerNVirtual()

Member Data Documentation

◆ fgLimitsFinder