class ROOT::Math::BrentMinimizer1D: private ROOT::Math::IMinimizer1D


   User class for performing function minimization

   It will use the Brent Method for function minimization in a given interval.
   This class is implemented from TF1::GetMinimum.

   To use the class, three steps have to be taken:
       1. Create the class.
       2. Set a function within an interval to look for the minimum.
       3. Call the Minimize function with the error parameters.

   If another minimization is to be performed, repeat the last two steps.

   @ingroup Minimization

Function Members (Methods)

public:

virtual	~BrentMinimizer1D()
ROOT::Math::BrentMinimizer1D	BrentMinimizer1D()
ROOT::Math::BrentMinimizer1D	BrentMinimizer1D(const ROOT::Math::BrentMinimizer1D&)
virtual double	FValLower() const
virtual double	FValMinimum() const
virtual double	FValUpper() const
virtual int	Iterations() const
virtual int	Minimize(int maxIter, double absTol, double relTol)
virtual const char*	Name() const
int	SetFunction(const ROOT::Math::IGenFunction& f, double xlow, double xup)
virtual double	XLower() const
virtual double	XMinimum() const
virtual double	XUpper() const

Data Members

protected:

const ROOT::Math::IGenFunction*	fFunction	Pointer to the function.
int	fNIter	Number of iterations needed for the last stimation.
double	fXMax	Upper bound of the search interval
double	fXMin	Lower bound of the search interval.
double	fXMinimum	Position of the stimated minimum.

Class Charts

Function documentation

virtual ~BrentMinimizer1D()

 Default Destructor.

double XMinimum()

 Return current estimate of the position of the minimum.

double XLower()

 Return current lower bound of the minimization interval.

double XUpper()

 Return current upper bound of the minimization interval.

double FValMinimum()

 Return function value at current estimate of the minimum.

double FValLower()

 Return function value at current lower bound of the minimization interval.

double FValUpper()

 Return function value at current upper bound of the minimization interval.

int Minimize(int maxIter, double absTol, double relTol)

 Find minimum position iterating until convergence specified by the absolute and relative tolerance or
          the maximum number of iteration is reached.

          \@param maxIter maximum number of iterations.
          \@param absTol desired absolute error in the minimum position.
          \@param absTol desired relative error in the minimum position.

int Iterations()

 Return number of iteration used to find minimum

const char * Name()

 Return name of minimization algorithm ("BrentMinimizer1D")

int SetFunction(const ROOT::Math::IGenFunction& f, double xlow, double xup)

 Sets function to be minimized.

          \@param f Function to be minimized.
          \@param xlow Lower bound of the search interval.
          \@param xup Upper bound of the search interval.