class ROOT::Math::BrentRootFinder: public ROOT::Math::IRootFinderMethod


   User class for finding function roots.

   It will use the Brent Method for finding function roots in a given interval.
   This class is implemented from TF1::GetX() method.

   @ingroup RootFind

Function Members (Methods)

public:

virtual	~BrentRootFinder()
ROOT::Math::BrentRootFinder	BrentRootFinder()
ROOT::Math::BrentRootFinder	BrentRootFinder(const ROOT::Math::BrentRootFinder&)
virtual int	ROOT::Math::IRootFinderMethod::Iterate()
virtual int	ROOT::Math::IRootFinderMethod::Iterations() const
virtual const char*	Name() const
ROOT::Math::IRootFinderMethod&	ROOT::Math::IRootFinderMethod::operator=(const ROOT::Math::IRootFinderMethod&)
virtual double	Root() const
virtual int	SetFunction(const ROOT::Math::IGenFunction& f, double xlow, double xup)
virtual int	Solve(int maxIter = 100, double absTol = 1E-3, double relTol = 1E-6)

Data Members

protected:

const ROOT::Math::IGenFunction*	fFunction	Pointer to the function.
double	fRoot	Current stimation of the function root.
double	fXMax	Upper bound of the search interval
double	fXMin	Lower bound of the search interval.

Class Charts

Function documentation

virtual ~BrentRootFinder()

 Default Destructor.

BrentRootFinder(const ROOT::Math::BrentRootFinder& )

 Default Constructor.

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

int Solve(int maxIter = 100, double absTol = 1E-3, double relTol = 1E-6)

 Returns the X value corresponding to the function value fy for (xmin<x<xmax).
          Method:
          First, the grid search is used to bracket the maximum
          with the step size = (xmax-xmin)/fNpx. This way, the step size
          can be controlled via the SetNpx() function. If the function is
          unimodal or if its extrema are far apart, setting the fNpx to
          a small value speeds the algorithm up many times.
          Then, Brent's method is applied on the bracketed interval.

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

double Root()

 Returns root value. Need to call first Solve().

const char* Name()

 Return name of root finder algorithm ("BrentRootFinder").