ROOT   6.08/07 Reference Guide
ROOT::Minuit2::GaussFcn2 Class Reference

Definition at line 22 of file GaussFcn2.h.

## Public Member Functions

GaussFcn2 (const std::vector< double > &meas, const std::vector< double > &pos, const std::vector< double > &mvar)

~GaussFcn2 ()

virtual double ErrorDef () const
Error definition of the function. More...

virtual void Init ()

std::vector< double > Measurements () const

virtual double operator() (const std::vector< double > &) const
The meaning of the vector of parameters is of course defined by the user, who uses the values of those parameters to calculate their function Value. More...

std::vector< double > Positions () const

virtual double Up () const
Error definition of the function. More...

std::vector< double > Variances () const

Public Member Functions inherited from ROOT::Minuit2::FCNBase
virtual ~FCNBase ()

virtual void SetErrorDef (double)
add interface to set dynamically a new error definition Re-implement this function if needed. More...

Public Member Functions inherited from ROOT::Minuit2::GenericFunction
virtual ~GenericFunction ()

## Private Attributes

std::vector< double > fMeasurements

double fMin

std::vector< double > fMVariances

std::vector< double > fPositions

#include </mnt/build/workspace/root-makedoc-v608/rootspi/rdoc/src/v6-08-00-patches/math/minuit2/test/MnSim/GaussFcn2.h>

Inheritance diagram for ROOT::Minuit2::GaussFcn2:
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## ◆ GaussFcn2()

 ROOT::Minuit2::GaussFcn2::GaussFcn2 ( const std::vector< double > & meas, const std::vector< double > & pos, const std::vector< double > & mvar )
inline

Definition at line 26 of file GaussFcn2.h.

## ◆ ~GaussFcn2()

 ROOT::Minuit2::GaussFcn2::~GaussFcn2 ( )
inline

Definition at line 32 of file GaussFcn2.h.

## ◆ ErrorDef()

 virtual double ROOT::Minuit2::GaussFcn2::ErrorDef ( ) const
inlinevirtual

Error definition of the function.

MINUIT defines Parameter errors as the change in Parameter Value required to change the function Value by up. Normally, for chisquared fits it is 1, and for negative log likelihood, its Value is 0.5. If the user wants instead the 2-sigma errors for chisquared fits, it becomes 4, as Chi2(x+n*sigma) = Chi2(x) + n*n.

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Reimplemented from ROOT::Minuit2::FCNBase.

Definition at line 38 of file GaussFcn2.h.

## ◆ Init()

 void ROOT::Minuit2::GaussFcn2::Init ( )
virtual

Definition at line 37 of file GaussFcn2.cxx.

## ◆ Measurements()

 std::vector ROOT::Minuit2::GaussFcn2::Measurements ( ) const
inline

Definition at line 40 of file GaussFcn2.h.

## ◆ operator()()

 double ROOT::Minuit2::GaussFcn2::operator() ( const std::vector< double > & x ) const
virtual

The meaning of the vector of parameters is of course defined by the user, who uses the values of those parameters to calculate their function Value.

The order and the position of these parameters is strictly the one specified by the user when supplying the starting values for minimization. The starting values must be specified by the user, either via an std::vector<double> or the MnUserParameters supplied as input to the MINUIT minimizers such as VariableMetricMinimizer or MnMigrad. Later values are determined by MINUIT as it searches for the Minimum or performs whatever analysis is requested by the user.

Parameters
 par function parameters as defined by the user.
Returns
the Value of the function.
MnUserParameters
VariableMetricMinimizer

Implements ROOT::Minuit2::FCNBase.

Definition at line 21 of file GaussFcn2.cxx.

## ◆ Positions()

 std::vector ROOT::Minuit2::GaussFcn2::Positions ( ) const
inline

Definition at line 41 of file GaussFcn2.h.

## ◆ Up()

 virtual double ROOT::Minuit2::GaussFcn2::Up ( ) const
inlinevirtual

Error definition of the function.

MINUIT defines Parameter errors as the change in Parameter Value required to change the function Value by up. Normally, for chisquared fits it is 1, and for negative log likelihood, its Value is 0.5. If the user wants instead the 2-sigma errors for chisquared fits, it becomes 4, as Chi2(x+n*sigma) = Chi2(x) + n*n.

Implements ROOT::Minuit2::FCNBase.

Definition at line 36 of file GaussFcn2.h.

## ◆ Variances()

 std::vector ROOT::Minuit2::GaussFcn2::Variances ( ) const
inline

Definition at line 42 of file GaussFcn2.h.

## ◆ fMeasurements

 std::vector ROOT::Minuit2::GaussFcn2::fMeasurements
private

Definition at line 46 of file GaussFcn2.h.

## ◆ fMin

 double ROOT::Minuit2::GaussFcn2::fMin
private

Definition at line 49 of file GaussFcn2.h.

## ◆ fMVariances

 std::vector ROOT::Minuit2::GaussFcn2::fMVariances
private

Definition at line 48 of file GaussFcn2.h.

## ◆ fPositions

 std::vector ROOT::Minuit2::GaussFcn2::fPositions
private

Definition at line 47 of file GaussFcn2.h.

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