FunctionGradient.h

Go to the documentation of this file.

// @(#)root/minuit2:$Id$
// Authors: M. Winkler, F. James, L. Moneta, A. Zsenei   2003-2005
 
/**********************************************************************
 *                                                                    *
 * Copyright (c) 2005 LCG ROOT Math team,  CERN/PH-SFT                *
 *                                                                    *
 **********************************************************************/
 
#ifndef ROOT_Minuit2_FunctionGradient
#define ROOT_Minuit2_FunctionGradient
 
#include "Minuit2/MnMatrix.h"
 
#include <memory>
 
namespace ROOT {
 
namespace Minuit2 {
 
class FunctionGradient {
 
private:
public:
   explicit FunctionGradient(unsigned int n)
      : fPtr{new Data{MnAlgebraicVector(n), MnAlgebraicVector(n), MnAlgebraicVector(n), false, false}}
   {
   }
 
   explicit FunctionGradient(const MnAlgebraicVector &grd)
      : fPtr{new Data{grd, MnAlgebraicVector(grd.size()), MnAlgebraicVector(grd.size()), true, true}}
   {
   }
 
   FunctionGradient(const MnAlgebraicVector &grd, const MnAlgebraicVector &g2, const MnAlgebraicVector &gstep)
      : fPtr{new Data{grd, g2, gstep, true, false}}
   {
   }
 
   const MnAlgebraicVector &Grad() const { return fPtr->fGradient; }
   const MnAlgebraicVector &Vec() const { return Grad(); }
   bool IsValid() const { return fPtr->fValid; }
 
   bool IsAnalytical() const { return fPtr->fAnalytical; }
   const MnAlgebraicVector &G2() const { return fPtr->fG2ndDerivative; }
   const MnAlgebraicVector &Gstep() const { return fPtr->fGStepSize; }
 
private:
   struct Data {
      MnAlgebraicVector fGradient;
      MnAlgebraicVector fG2ndDerivative;
      MnAlgebraicVector fGStepSize;
      bool fValid;
      bool fAnalytical;
   };
 
   std::shared_ptr<Data> fPtr;
};
 
} // namespace Minuit2
 
} // namespace ROOT
 
#endif // ROOT_Minuit2_FunctionGradient