root/Minuit2/SimplexParameters.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_SimplexParameters
0011 #define ROOT_Minuit2_SimplexParameters
0012
0013 #include <cassert>
0014
0015 #include "Minuit2/MnMatrix.h"
0016
0017 #include <ROOT/RSpan.hxx>
0018
0019 #include <vector>
0020 #include <utility>
0021
0022 namespace ROOT {
0023
0024 namespace Minuit2 {
0025
0026 /**
0027    class describing the simplex set of points (f(x), x )  which evolve during the minimization
0028    iteration process.
0029  */
0030
0031 class SimplexParameters {
0032
0033 public:
0034    SimplexParameters(std::span<const std::pair<double, MnAlgebraicVector>> simpl, unsigned int jh, unsigned int jl)
0035       : fSimplexParameters(simpl.begin(), simpl.end()), fJHigh(jh), fJLow(jl)
0036    {
0037    }
0038
0039    void Update(double, const MnAlgebraicVector &);
0040
0041    const std::vector<std::pair<double, MnAlgebraicVector>> &Simplex() const { return fSimplexParameters; }
0042
0043    const std::pair<double, MnAlgebraicVector> &operator()(unsigned int i) const
0044    {
0045       assert(i < fSimplexParameters.size());
0046       return fSimplexParameters[i];
0047    }
0048
0049    unsigned int Jh() const { return fJHigh; }
0050    unsigned int Jl() const { return fJLow; }
0051    double Edm() const { return fSimplexParameters[Jh()].first - fSimplexParameters[Jl()].first; }
0052    MnAlgebraicVector Dirin() const;
0053
0054 private:
0055    std::vector<std::pair<double, MnAlgebraicVector>> fSimplexParameters;
0056    unsigned int fJHigh;
0057    unsigned int fJLow;
0058 };
0059
0060 } // namespace Minuit2
0061
0062 } // namespace ROOT
0063
0064 #endif // ROOT_Minuit2_SimplexParameters