// @(#)root/minuit:$Id$ // Author: L. Moneta Wed Oct 25 16:28:55 2006 /********************************************************************** * * * Copyright (c) 2006 LCG ROOT Math Team, CERN/PH-SFT * * * * * **********************************************************************/ // Header file for class TMinuitMinimizer #ifndef ROOT_TMinuitMinimizer #define ROOT_TMinuitMinimizer #ifndef ROOT_Math_Minimizer #include "Math/Minimizer.h" #endif #ifndef ROOT_Rtypes #include "Rtypes.h" #endif class TMinuit; namespace ROOT { namespace Minuit { // enumeration specifying the type of TMinuit minimizers enum EMinimizerType { kMigrad, kSimplex, kCombined, kMigradImproved, kScan, kSeek }; } } /** TMinuitMinimizer class: minimizer implementation based on TMinuit. */ class TMinuitMinimizer : public ROOT::Math::Minimizer { public: /** Default constructor */ TMinuitMinimizer ( ROOT::Minuit::EMinimizerType type = ROOT::Minuit::kMigrad, unsigned int ndim = 0); /** Constructor from a char * (used by PM) */ TMinuitMinimizer ( const char * type , unsigned int ndim = 0); /** Destructor (no operations) */ ~TMinuitMinimizer (); private: // usually copying is non trivial, so we make this unaccessible /** Copy constructor */ TMinuitMinimizer(const TMinuitMinimizer &); /** Assignment operator */ TMinuitMinimizer & operator = (const TMinuitMinimizer & rhs); public: /// set the function to minimize virtual void SetFunction(const ROOT::Math::IMultiGenFunction & func); /// set the function to minimize virtual void SetFunction(const ROOT::Math::IMultiGradFunction & func); /// set free variable virtual bool SetVariable(unsigned int ivar, const std::string & name, double val, double step); /// set upper/lower limited variable (override if minimizer supports them ) virtual bool SetLimitedVariable(unsigned int ivar , const std::string & name , double val , double step , double /* lower */, double /* upper */); /// set lower limit variable (override if minimizer supports them ) virtual bool SetLowerLimitedVariable(unsigned int ivar , const std::string & name , double val , double step , double lower ); /// set upper limit variable (override if minimizer supports them ) virtual bool SetUpperLimitedVariable(unsigned int ivar , const std::string & name , double val , double step , double upper ); /// set fixed variable (override if minimizer supports them ) virtual bool SetFixedVariable(unsigned int /* ivar */, const std::string & /* name */, double /* val */); /// set the value of an existing variable virtual bool SetVariableValue(unsigned int , double ); /// method to perform the minimization virtual bool Minimize(); /// return minimum function value virtual double MinValue() const; /// return expected distance reached from the minimum virtual double Edm() const; /// return pointer to X values at the minimum virtual const double * X() const { return &fParams.front(); } /// return pointer to gradient values at the minimum virtual const double * MinGradient() const { return 0; } // not available in Minuit2 /// number of function calls to reach the minimum virtual unsigned int NCalls() const; /// this is <= Function().NDim() which is the total /// number of variables (free+ constrained ones) virtual unsigned int NDim() const { return fDim; } /// number of free variables (real dimension of the problem) /// this is <= Function().NDim() which is the total virtual unsigned int NFree() const; /// minimizer provides error and error matrix virtual bool ProvidesError() const { return true; } /// return errors at the minimum virtual const double * Errors() const { return &fErrors.front(); } /** return covariance matrices elements if the variable is fixed the matrix is zero The ordering of the variables is the same as in errors */ virtual double CovMatrix(unsigned int i, unsigned int j) const { return ( fCovar.size() > (i + fDim* j) ) ? fCovar[i + fDim* j] : 0; } /** Fill the passed array with the covariance matrix elements if the variable is fixed or const the value is zero. The array will be filled as cov[i *ndim + j] The ordering of the variables is the same as in errors and parameter value. This is different from the direct interface of Minuit2 or TMinuit where the values were obtained only to variable parameters */ virtual bool GetCovMatrix(double * cov) const; /** Fill the passed array with the Hessian matrix elements The Hessian matrix is the matrix of the second derivatives and is the inverse of the covariance matrix If the variable is fixed or const the values for that variables are zero. The array will be filled as h[i *ndim + j] */ virtual bool GetHessianMatrix(double * h) const; ///return status of covariance matrix virtual int CovMatrixStatus() const; ///global correlation coefficient for variable i virtual double GlobalCC(unsigned int ) const; /// minos error for variable i, return false if Minos failed virtual bool GetMinosError(unsigned int i, double & errLow, double & errUp, int = 0); /** perform a full calculation of the Hessian matrix for error calculation */ virtual bool Hesse(); /** scan a parameter i around the minimum. A minimization must have been done before, return false if it is not the case */ virtual bool Scan(unsigned int i, unsigned int &nstep, double * x, double * y, double xmin = 0, double xmax = 0); /** find the contour points (xi,xj) of the function for parameter i and j around the minimum The contour will be find for value of the function = Min + ErrorUp(); */ virtual bool Contour(unsigned int i, unsigned int j, unsigned int & npoints, double *xi, double *xj); virtual void PrintResults(); /// return reference to the objective function ///virtual const ROOT::Math::IGenFunction & Function() const; /// get name of variables (override if minimizer support storing of variable names) virtual std::string VariableName(unsigned int ivar) const; /// get index of variable given a variable given a name /// return always -1 . (It is Not implemented) virtual int VariableIndex(const std::string & name) const; /// static function to switch on/off usage of static global TMinuit instance (gMinuit) /// By default it is used (i.e. is on). Method returns the previous state bool static UseStaticMinuit(bool on = true); /// suppress the minuit warnings (if called with false will enable them) /// By default they are suppressed only when the printlevel is <= 0 void SuppressMinuitWarnings(bool nowarn=true); protected: /// implementation of FCN for Minuit static void Fcn( int &, double * , double & f, double * , int); /// implementation of FCN for Minuit when user provided gradient is used static void FcnGrad( int &, double * g, double & f, double * , int); /// initialize the TMinuit instance void InitTMinuit(int ndim); /// reset void DoClear(); ///release a parameter that is fixed when it is redefined void DoReleaseFixParameter( int ivar); /// retrieve minimum parameters and errors from TMinuit void RetrieveParams(); /// retrieve error matrix from TMinuit void RetrieveErrorMatrix(); private: bool fUsed; bool fMinosRun; unsigned int fDim; std::vector fParams; std::vector fErrors; std::vector fCovar; ROOT::Minuit::EMinimizerType fType; TMinuit * fMinuit; // need to have a static copy of the function //NOTE: This is NOT thread safe. static ROOT::Math::IMultiGenFunction * fgFunc; static TMinuit * fgMinuit; static bool fgUsed; // flag to control if static instance has done minimization static bool fgUseStaticMinuit; // flag to control if using global TMInuit instance (gMinuit) ClassDef(TMinuitMinimizer,1) //Implementation of Minimizer interface using TMinuit }; #endif /* ROOT_TMinuitMinimizer */