Class implementing the thermal model fit procedure. More...

#include <ThermalModelFit.h>

Public Member Functions
	ThermalModelFit (ThermalModelBase *model)
	Construct a new ThermalModelFit object.

	~ThermalModelFit (void)
	Destroy the Thermal Model Fit object.

void	SetFitFlag (const std::string &name, bool flag)
	Set whether FitParameter with a given name should be fitted.

void	SetData (const std::vector< FittedQuantity > &inData)
	Sets the data to fit.

void	SetQuantities (const std::vector< FittedQuantity > &inQuantities)
	Same as SetData()

void	AddData (const std::vector< FittedQuantity > &inData)
	Add more data to fit.

void	AddQuantities (const std::vector< FittedQuantity > &inQuantities)
	Same as AddData()

void	AddDataPoint (const FittedQuantity &inDataPoint)
	Add one more data point to fit.

void	AddQuantity (const FittedQuantity &inQuantity)
	Same as AddDataPoint()

void	ClearData ()
	Clear the fitted data.

void	ClearQuantities ()
	Same as ClearData()

void	SetRatios (const std::vector< ExperimentRatio > &inRatios)

void	AddRatios (const std::vector< ExperimentRatio > &inRatios)

void	AddRatio (const ExperimentRatio &inRatio)

void	ClearRatios ()

void	PrintRatios ()

void	SetMultiplicities (const std::vector< ExperimentMultiplicity > &inMultiplicities)

void	AddMultiplicities (const std::vector< ExperimentMultiplicity > &inMultiplicities)

void	AddMultiplicity (const ExperimentMultiplicity &inMultiplicity)

void	ClearMultiplicities ()

void	PrintParameters ()
	Print function.

void	PrintMultiplicities ()

void	PrintYields ()

void	PrintYieldsTable (std::string filename="Yield.dat")

void	PrintYieldsTable2 (std::string filename="Yield.dat")

void	PrintYieldsLatex (std::string filename="Yield.dat", std::string name="A+A")

void	PrintYieldsLatexAll (std::string filename="Yield.dat", std::string name="A+A", bool asymm=false)

void	PrintFitLog (std::string filename="", std::string comment="Thermal fit", bool asymm=false)
	Prints the result of the fitting procedure to a file.

ThermalModelFitParameters	PerformFit (bool verbose=true, bool AsymmErrors=false)
	The thermal fit procedure.

int	GetNdf () const
	Number of degrees of freedom in the fit.

void	Increment ()
	Used by MINUIT.

const ThermalModelFitParameters &	Parameters () const

void	SetParameters (const ThermalModelFitParameters &params)
	Sets the fit parameters.

void	SetParameter (const std::string &name, const FitParameter &param)
	Sets the fit parameter with a given name.

void	SetParameter (const std::string &name, double val, double err, double xmin, double xmax)
	Sets the fit parameter with a given name.

void	SetParameterValue (const std::string &name, double value)
	Sets the (initial) value for the fit parameter with a given name.

void	SetParameterFitFlag (const std::string &name, bool toFit)
	Sets whether the fit parameter with a given name is fitted.

const ThermalModelFitParametersExtended &	ExtendedParameters () const

ThermalModelBase *	model ()

ThermalModelPCE *	modelpce ()

void	SetSBConstraint (double SB)

void	SetQBConstraint (double QB)

double	SoverB () const

double	QoverB () const

const std::vector< ExperimentMultiplicity > &	Multiplicities () const

const std::vector< ExperimentRatio > &	Ratios () const

const std::vector< FittedQuantity > &	FittedQuantities () const
	Return a vector of the fitted quantities (data)

void	FixVcOverV (bool fix)

bool	FixVcOverV () const

void	SetVcOverV (double VcOverV)

double	VcOverV () const

void	UseTkin (bool YieldsAtTkin)
	Sets whether the yields should be evaluated at Tkin using partial chemical equilibrium.

bool	UseTkin () const

void	UseSahaForNuclei (bool UseSaha)
	Sets whether the nuclear abundances are evaluated in PCE using the Saha equation.

void	PCEFreezeLongLived (bool FreezeLongLived)
	Sets whether the yields of long-lived resonance are frozen in the PCE.

void	SetPCEWidthCut (double WidthCut)
	Sets the resonance width cut for freezeing the yields of long-lived resonances.

void	PCEAnnihilation (bool Annihilation)
	Sets whether to include baryon annihilation in PCE.

void	SetPCEPionAnnihilationNumber (double PionAnnihilationNumber)
	Sets the average number of pions in baryon annihilation.

std::pair< double, double >	ModelDescriptionAccuracy () const
	Returns a relative error of the data description (and its uncertainty estimate)


int &	Iters ()

double &	Chi2 ()

double &	BT ()

double &	QT ()

double &	ST ()

double &	CT ()

double &	ModelData (int index)

int	ModelDataSize () const

void	ClearModelData ()

int &	Ndf ()

Static Public Member Functions
static std::vector< FittedQuantity >	loadExpDataFromFile (const std::string &filename)
	Load the experimental data from a file.

static void	saveExpDataToFile (const std::vector< FittedQuantity > &outQuantities, const std::string &filename)

Detailed Description

Class implementing the thermal model fit procedure.

Performs a fit within a generic HRG model to a set of measured multiplicities and/or yield ratios. This is achieved by minimizing

\[ \chi^2 = \frac{\chi^2}{N_{\rm dof}} ~=~\frac{1}{N_{\rm dof}}\sum_{i=1}^N\frac{\left(N_i^{\rm exp}~-~N_i^{\rm HRG}\right)^2}{\sigma_i^2} \]

with MINUIT2.

The actual HRG model to use is provided through a pointer to the corresponding thermalfist::ThermalModelBase object in the constructor.

The fitted thermal parameters can be specified in a thermalfist::ThermalModelFitParameters object and should be provided through the SetParameters() method.

The data to fit can be specified as vector of FittedQuantity objects. It can be provided through the SetQuantities() method, the data can be read from a file with loadExpDataFromFile().

Finally, the fit procedure is invoked through the PerformFit() method.

Examples: BagModelFit.cpp, cpc2-chi2-vs-T.cpp, and cpc3-chi2NEQ.cpp.

Definition at line 51 of file ThermalModelFit.h.

Constructor & Destructor Documentation

◆ ThermalModelFit()

thermalfist::ThermalModelFit::ThermalModelFit ( ThermalModelBase * model )

Construct a new ThermalModelFit object.

Parameters

model Pointer to the ThermalModelBase object which implements the HRG model to use in fits

Definition at line 214 of file ThermalModelFit.cpp.

◆ ~ThermalModelFit()

thermalfist::ThermalModelFit::~ThermalModelFit ( void )

Destroy the Thermal Model Fit object.

Definition at line 222 of file ThermalModelFit.cpp.

Member Function Documentation

◆ AddData()

void thermalfist::ThermalModelFit::AddData ( const std::vector< FittedQuantity > & inData )

inline

Add more data to fit.

Parameters

inData A vector of additional measurements to fit

Definition at line 92 of file ThermalModelFit.h.

◆ AddDataPoint()

void thermalfist::ThermalModelFit::AddDataPoint ( const FittedQuantity & inDataPoint )

inline

Add one more data point to fit.

Parameters

inDataPoint Data point to fit

Definition at line 103 of file ThermalModelFit.h.

◆ AddMultiplicities()

void thermalfist::ThermalModelFit::AddMultiplicities ( const std::vector< ExperimentMultiplicity > & inMultiplicities )

inline

Definition at line 146 of file ThermalModelFit.h.

◆ AddMultiplicity()

void thermalfist::ThermalModelFit::AddMultiplicity ( const ExperimentMultiplicity & inMultiplicity )

inline

Definition at line 153 of file ThermalModelFit.h.

◆ AddQuantities()

void thermalfist::ThermalModelFit::AddQuantities ( const std::vector< FittedQuantity > & inQuantities )

inline

Same as AddData()

Definition at line 98 of file ThermalModelFit.h.

◆ AddQuantity()

void thermalfist::ThermalModelFit::AddQuantity ( const FittedQuantity & inQuantity )

inline

Same as AddDataPoint()

Definition at line 112 of file ThermalModelFit.h.

◆ AddRatio()

void thermalfist::ThermalModelFit::AddRatio ( const ExperimentRatio & inRatio )

inline

Definition at line 133 of file ThermalModelFit.h.

◆ AddRatios()

void thermalfist::ThermalModelFit::AddRatios ( const std::vector< ExperimentRatio > & inRatios )

inline

Definition at line 126 of file ThermalModelFit.h.

◆ BT()

double & thermalfist::ThermalModelFit::BT ( )

inline

Definition at line 275 of file ThermalModelFit.h.

◆ Chi2()

double & thermalfist::ThermalModelFit::Chi2 ( )

inline

Definition at line 273 of file ThermalModelFit.h.

◆ ClearData()

void thermalfist::ThermalModelFit::ClearData ( )

inline

Clear the fitted data.

Definition at line 115 of file ThermalModelFit.h.

◆ ClearModelData()

void thermalfist::ThermalModelFit::ClearModelData ( )

inline

Definition at line 287 of file ThermalModelFit.h.

◆ ClearMultiplicities()

void thermalfist::ThermalModelFit::ClearMultiplicities ( )

inline

Definition at line 158 of file ThermalModelFit.h.

◆ ClearQuantities()

void thermalfist::ThermalModelFit::ClearQuantities ( )

inline

Same as ClearData()

Definition at line 118 of file ThermalModelFit.h.

◆ ClearRatios()

void thermalfist::ThermalModelFit::ClearRatios ( )

inline

Definition at line 138 of file ThermalModelFit.h.

◆ CT()

double & thermalfist::ThermalModelFit::CT ( )

inline

Definition at line 281 of file ThermalModelFit.h.

◆ ExtendedParameters()

const ThermalModelFitParametersExtended & thermalfist::ThermalModelFit::ExtendedParameters ( ) const

inline

Definition at line 226 of file ThermalModelFit.h.

◆ FittedQuantities()

const std::vector< FittedQuantity > & thermalfist::ThermalModelFit::FittedQuantities ( ) const

inline

Return a vector of the fitted quantities (data)

Definition at line 266 of file ThermalModelFit.h.

◆ FixVcOverV() [1/2]

bool thermalfist::ThermalModelFit::FixVcOverV ( ) const

inline

Definition at line 296 of file ThermalModelFit.h.

◆ FixVcOverV() [2/2]

void thermalfist::ThermalModelFit::FixVcOverV ( bool fix )

inline

Whether the correlation volume is tied to the total volume or an independent parameter.

Definition at line 295 of file ThermalModelFit.h.

◆ GetNdf()

int thermalfist::ThermalModelFit::GetNdf ( ) const

Number of degrees of freedom in the fit.

Definition at line 1425 of file ThermalModelFit.cpp.

◆ Increment()

void thermalfist::ThermalModelFit::Increment ( )

inline

Used by MINUIT.

Definition at line 204 of file ThermalModelFit.h.

◆ Iters()

int & thermalfist::ThermalModelFit::Iters ( )

inline

Used for real-time monitoring in the GUI.

Definition at line 271 of file ThermalModelFit.h.

◆ loadExpDataFromFile()

std::vector< FittedQuantity > thermalfist::ThermalModelFit::loadExpDataFromFile ( const std::string & filename )

static

Load the experimental data from a file.

Definition at line 1274 of file ThermalModelFit.cpp.

◆ model()

ThermalModelBase * thermalfist::ThermalModelFit::model ( )

inline

Pointer to a ThermalModelBase object implementing the HRG model used

Definition at line 230 of file ThermalModelFit.h.

◆ ModelData()

double & thermalfist::ThermalModelFit::ModelData ( int index )

inline

Definition at line 283 of file ThermalModelFit.h.

◆ ModelDataSize()

int thermalfist::ThermalModelFit::ModelDataSize ( ) const

inline

Definition at line 285 of file ThermalModelFit.h.

◆ ModelDescriptionAccuracy()

std::pair< double, double > thermalfist::ThermalModelFit::ModelDescriptionAccuracy ( ) const

Returns a relative error of the data description (and its uncertainty estimate)

Definition at line 1243 of file ThermalModelFit.cpp.

◆ modelpce()

ThermalModelPCE * thermalfist::ThermalModelFit::modelpce ( )

inline

Pointer to a ThermalModelBase object implementing the partial chemical equilibrium HRG model used

Definition at line 234 of file ThermalModelFit.h.

◆ Multiplicities()

const std::vector< ExperimentMultiplicity > & thermalfist::ThermalModelFit::Multiplicities ( ) const

inline

Return a vector of the fitted multiplicities (yields) Ignores the ratios

Definition at line 259 of file ThermalModelFit.h.

◆ Ndf()

int & thermalfist::ThermalModelFit::Ndf ( )

inline

Definition at line 289 of file ThermalModelFit.h.

◆ Parameters()

const ThermalModelFitParameters & thermalfist::ThermalModelFit::Parameters ( ) const

inline

Current fit parameters. Contains the fit result after PerformFit() was called.

Definition at line 208 of file ThermalModelFit.h.

◆ PCEAnnihilation()

void thermalfist::ThermalModelFit::PCEAnnihilation ( bool Annihilation )

inline

Sets whether to include baryon annihilation in PCE.

Definition at line 322 of file ThermalModelFit.h.

◆ PCEFreezeLongLived()

void thermalfist::ThermalModelFit::PCEFreezeLongLived ( bool FreezeLongLived )

inline

Sets whether the yields of long-lived resonance are frozen in the PCE.

Definition at line 316 of file ThermalModelFit.h.

◆ PerformFit()

ThermalModelFitParameters thermalfist::ThermalModelFit::PerformFit	(	bool	verbose = true,
		bool	AsymmErrors = false )

The thermal fit procedure.

Performs a thermal fit of thermal parameters, specified by SetParameters(), to the experimental data, provided through SetQuantities(), within a HRG model provided by a pointer to thermalfist::ThermalModelBase in constructor.

Returns a thermalfist::ThermalModelFitParameters parameters object containing the values and errors of the fitted thermal parameters resulting from \( \chi^2 \) minimization.

Parameters

verbose	If true, additional output is shown on screen during the fitting
AsymmErrors	If true, asymmetric error bars are computed

Returns: ThermalModelFitParameters The fitted parameters

Examples: BagModelFit.cpp, cpc2-chi2-vs-T.cpp, and cpc3-chi2NEQ.cpp.

Definition at line 226 of file ThermalModelFit.cpp.

◆ PrintFitLog()

void thermalfist::ThermalModelFit::PrintFitLog	(	std::string	filename = "",
		std::string	comment = "Thermal fit",
		bool	asymm = false )

Prints the result of the fitting procedure to a file.

Examples: BagModelFit.cpp.

Definition at line 989 of file ThermalModelFit.cpp.

◆ PrintMultiplicities()

void thermalfist::ThermalModelFit::PrintMultiplicities ( )

Definition at line 601 of file ThermalModelFit.cpp.

◆ PrintParameters()

void thermalfist::ThermalModelFit::PrintParameters ( )

Print function.

Definition at line 582 of file ThermalModelFit.cpp.

◆ PrintRatios()

void thermalfist::ThermalModelFit::PrintRatios ( )

Definition at line 564 of file ThermalModelFit.cpp.

◆ PrintYields()

void thermalfist::ThermalModelFit::PrintYields ( )

Definition at line 633 of file ThermalModelFit.cpp.

◆ PrintYieldsLatex()

void thermalfist::ThermalModelFit::PrintYieldsLatex	(	std::string	filename = "Yield.dat",
		std::string	name = "A+A" )

Definition at line 770 of file ThermalModelFit.cpp.

◆ PrintYieldsLatexAll()

void thermalfist::ThermalModelFit::PrintYieldsLatexAll	(	std::string	filename = "Yield.dat",
		std::string	name = "A+A",
		bool	asymm = false )

Definition at line 829 of file ThermalModelFit.cpp.

◆ PrintYieldsTable()

void thermalfist::ThermalModelFit::PrintYieldsTable ( std::string filename = "Yield.dat" )

Definition at line 686 of file ThermalModelFit.cpp.

◆ PrintYieldsTable2()

void thermalfist::ThermalModelFit::PrintYieldsTable2 ( std::string filename = "Yield.dat" )

Definition at line 735 of file ThermalModelFit.cpp.

◆ QoverB()

double thermalfist::ThermalModelFit::QoverB ( ) const

inline

Deprecated

Definition at line 255 of file ThermalModelFit.h.

◆ QT()

double & thermalfist::ThermalModelFit::QT ( )

inline

Definition at line 277 of file ThermalModelFit.h.

◆ Ratios()

const std::vector< ExperimentRatio > & thermalfist::ThermalModelFit::Ratios ( ) const

inline

Return a vector of the fitted yield ratios Ignores the multiplicities

Definition at line 263 of file ThermalModelFit.h.

◆ saveExpDataToFile()

void thermalfist::ThermalModelFit::saveExpDataToFile	(	const std::vector< FittedQuantity > &	outQuantities,
		const std::string &	filename )

static

Definition at line 1383 of file ThermalModelFit.cpp.

◆ SetData()

void thermalfist::ThermalModelFit::SetData ( const std::vector< FittedQuantity > & inData )

inline

Sets the data to fit.

Parameters

inData A vector of measurements to fit

Definition at line 79 of file ThermalModelFit.h.

◆ SetFitFlag()

void thermalfist::ThermalModelFit::SetFitFlag	(	const std::string &	name,
		bool	flag )

inline

Set whether FitParameter with a given name should be fitted.

Parameters

name	FitParameter name
flag	true – fitted, false – not fitted

Definition at line 71 of file ThermalModelFit.h.

◆ SetMultiplicities()

void thermalfist::ThermalModelFit::SetMultiplicities ( const std::vector< ExperimentMultiplicity > & inMultiplicities )

inline

Definition at line 142 of file ThermalModelFit.h.

◆ SetParameter() [1/2]

void thermalfist::ThermalModelFit::SetParameter	(	const std::string &	name,
		const FitParameter &	param )

inline

Sets the fit parameter with a given name.

Examples: BagModelFit.cpp, cpc2-chi2-vs-T.cpp, and cpc3-chi2NEQ.cpp.

Definition at line 214 of file ThermalModelFit.h.

◆ SetParameter() [2/2]

void thermalfist::ThermalModelFit::SetParameter	(	const std::string &	name,
		double	val,
		double	err,
		double	xmin,
		double	xmax )

inline

Sets the fit parameter with a given name.

Definition at line 217 of file ThermalModelFit.h.

◆ SetParameterFitFlag()

void thermalfist::ThermalModelFit::SetParameterFitFlag	(	const std::string &	name,
		bool	toFit )

inline

Sets whether the fit parameter with a given name is fitted.

Examples: BagModelFit.cpp, cpc2-chi2-vs-T.cpp, and cpc3-chi2NEQ.cpp.

Definition at line 223 of file ThermalModelFit.h.

◆ SetParameters()

void thermalfist::ThermalModelFit::SetParameters ( const ThermalModelFitParameters & params )

inline

Sets the fit parameters.

Definition at line 211 of file ThermalModelFit.h.

◆ SetParameterValue()

void thermalfist::ThermalModelFit::SetParameterValue	(	const std::string &	name,
		double	value )

inline

Sets the (initial) value for the fit parameter with a given name.

Examples: BagModelFit.cpp, and cpc2-chi2-vs-T.cpp.

Definition at line 220 of file ThermalModelFit.h.

◆ SetPCEPionAnnihilationNumber()

void thermalfist::ThermalModelFit::SetPCEPionAnnihilationNumber ( double PionAnnihilationNumber )

inline

Sets the average number of pions in baryon annihilation.

Definition at line 325 of file ThermalModelFit.h.

◆ SetPCEWidthCut()

void thermalfist::ThermalModelFit::SetPCEWidthCut ( double WidthCut )

inline

Sets the resonance width cut for freezeing the yields of long-lived resonances.

Definition at line 319 of file ThermalModelFit.h.

◆ SetQBConstraint()

void thermalfist::ThermalModelFit::SetQBConstraint ( double QB )

inline

Set the electric-to-baryon charge ratio constraint for \(\mu_Q \)

Deprecated: Electric-to-baryon charge ratio constraint should be set directly on a ThermalModelBase object

Definition at line 246 of file ThermalModelFit.h.

◆ SetQuantities()

void thermalfist::ThermalModelFit::SetQuantities ( const std::vector< FittedQuantity > & inQuantities )

inline

Same as SetData()

Examples: BagModelFit.cpp, cpc2-chi2-vs-T.cpp, and cpc3-chi2NEQ.cpp.

Definition at line 87 of file ThermalModelFit.h.

◆ SetRatios()

void thermalfist::ThermalModelFit::SetRatios ( const std::vector< ExperimentRatio > & inRatios )

inline

Deprecated: Use SetQuantities(), AddQuantities(), and AddQuantity() instead

Definition at line 122 of file ThermalModelFit.h.

◆ SetSBConstraint()

void thermalfist::ThermalModelFit::SetSBConstraint ( double SB )

inline

Set the entropy per baryon constraint for \(\mu_B \)

Deprecated: Entropy per baryon constraint should be set directly on a ThermalModelBase object

Definition at line 238 of file ThermalModelFit.h.

◆ SetVcOverV()

void thermalfist::ThermalModelFit::SetVcOverV ( double VcOverV )

inline

The value of the correlation volume over the total volume ratio, \( V_c / V \). If FixVcOverV() is set to true this value is used fix \( V_c \) by the total volume.

Definition at line 304 of file ThermalModelFit.h.

◆ SoverB()

double thermalfist::ThermalModelFit::SoverB ( ) const

inline

Deprecated

Definition at line 253 of file ThermalModelFit.h.

◆ ST()

double & thermalfist::ThermalModelFit::ST ( )

inline

Definition at line 279 of file ThermalModelFit.h.

◆ UseSahaForNuclei()

void thermalfist::ThermalModelFit::UseSahaForNuclei ( bool UseSaha )

inline

Sets whether the nuclear abundances are evaluated in PCE using the Saha equation.

Definition at line 313 of file ThermalModelFit.h.

◆ UseTkin() [1/2]

bool thermalfist::ThermalModelFit::UseTkin ( ) const

inline

Definition at line 310 of file ThermalModelFit.h.

◆ UseTkin() [2/2]

void thermalfist::ThermalModelFit::UseTkin ( bool YieldsAtTkin )

inline

Sets whether the yields should be evaluated at Tkin using partial chemical equilibrium.

Definition at line 309 of file ThermalModelFit.h.

◆ VcOverV()

double thermalfist::ThermalModelFit::VcOverV ( ) const

inline

Definition at line 305 of file ThermalModelFit.h.

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

include/HRGFit/ThermalModelFit.h
src/library/HRGFit/ThermalModelFit.cpp

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ThermalModelFit()

◆ ~ThermalModelFit()

Member Function Documentation

◆ AddData()

◆ AddDataPoint()

◆ AddMultiplicities()

◆ AddMultiplicity()

◆ AddQuantities()

◆ AddQuantity()

◆ AddRatio()

◆ AddRatios()

◆ BT()

◆ Chi2()

◆ ClearData()

◆ ClearModelData()

◆ ClearMultiplicities()

◆ ClearQuantities()

◆ ClearRatios()

◆ CT()

◆ ExtendedParameters()

◆ FittedQuantities()

◆ FixVcOverV() [1/2]

◆ FixVcOverV() [2/2]

◆ GetNdf()

◆ Increment()

◆ Iters()

◆ loadExpDataFromFile()

◆ model()

◆ ModelData()

◆ ModelDataSize()

◆ ModelDescriptionAccuracy()

◆ modelpce()

◆ Multiplicities()

◆ Ndf()

◆ Parameters()

◆ PCEAnnihilation()

◆ PCEFreezeLongLived()

◆ PerformFit()

◆ PrintFitLog()

◆ PrintMultiplicities()

◆ PrintParameters()

◆ PrintRatios()

◆ PrintYields()

◆ PrintYieldsLatex()

◆ PrintYieldsLatexAll()

◆ PrintYieldsTable()

◆ PrintYieldsTable2()

◆ QoverB()

◆ QT()

◆ Ratios()

◆ saveExpDataToFile()

◆ SetData()

◆ SetFitFlag()

◆ SetMultiplicities()

◆ SetParameter() [1/2]

◆ SetParameter() [2/2]

◆ SetParameterFitFlag()

◆ SetParameters()

◆ SetParameterValue()

◆ SetPCEPionAnnihilationNumber()

◆ SetPCEWidthCut()

◆ SetQBConstraint()

◆ SetQuantities()

◆ SetRatios()

◆ SetSBConstraint()

◆ SetVcOverV()

◆ SoverB()

◆ ST()

◆ UseSahaForNuclei()

◆ UseTkin() [1/2]

◆ UseTkin() [2/2]

◆ VcOverV()