root/Minuit2/FunctionGradient.h

0001 // @(#)root/minuit2:$Id$
0002 // Authors: M. Winkler, F. James, L. Moneta, A. Zsenei   2003-2005
0003
0004 /**********************************************************************
0005  *                                                                    *
0006  * Copyright (c) 2005 LCG ROOT Math team,  CERN/PH-SFT                *
0007  *                                                                    *
0008  **********************************************************************/
0009
0010 #ifndef ROOT_Minuit2_FunctionGradient
0011 #define ROOT_Minuit2_FunctionGradient
0012
0013 #include "Minuit2/MnMatrix.h"
0014
0015 #include <memory>
0016
0017 namespace ROOT {
0018
0019 namespace Minuit2 {
0020
0021 class FunctionGradient {
0022
0023 private:
0024 public:
0025    explicit FunctionGradient(unsigned int n)
0026       : fPtr{new Data{MnAlgebraicVector(n), MnAlgebraicVector(n), MnAlgebraicVector(n), false, false, false}}
0027    {
0028    }
0029
0030    explicit FunctionGradient(const MnAlgebraicVector &grd)
0031       : fPtr{new Data{grd, MnAlgebraicVector(0), MnAlgebraicVector(0), true, true, false}}
0032    {
0033    }
0034
0035    FunctionGradient(const MnAlgebraicVector &grd, const MnAlgebraicVector &g2)
0036       : fPtr{new Data{grd, g2, MnAlgebraicVector(0), true, true, true}}
0037    {
0038    }
0039
0040
0041    FunctionGradient(const MnAlgebraicVector &grd, const MnAlgebraicVector &g2, const MnAlgebraicVector &gstep)
0042       : fPtr{new Data{grd, g2, gstep, true, false, true}}
0043    {
0044    }
0045
0046    const MnAlgebraicVector &Grad() const { return fPtr->fGradient; }
0047    const MnAlgebraicVector &Vec() const { return Grad(); }
0048    bool IsValid() const { return fPtr->fValid; }
0049    bool IsAnalytical() const { return fPtr->fAnalytical; }
0050    bool HasG2() const { return fPtr->fHasG2; }
0051    const MnAlgebraicVector &G2() const { return fPtr->fG2ndDerivative; }
0052    const MnAlgebraicVector &Gstep() const { return fPtr->fGStepSize; }
0053
0054 private:
0055    struct Data {
0056       MnAlgebraicVector fGradient;
0057       MnAlgebraicVector fG2ndDerivative;
0058       MnAlgebraicVector fGStepSize;
0059       bool fValid;
0060       bool fAnalytical;
0061       bool fHasG2;
0062    };
0063
0064    std::shared_ptr<Data> fPtr;
0065 };
0066
0067 } // namespace Minuit2
0068
0069 } // namespace ROOT
0070
0071 #endif // ROOT_Minuit2_FunctionGradient