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Revision 25486 - (download) (as text) (annotate)
Mon Sep 22 12:43:03 2008 UTC (6 years, 4 months ago) by moneta
File size: 4290 byte(s)
import changes from math development branches for subdirectory math. List of changes in detail: 

mathcore: 
---------
  MinimizerOptions: 
	new  class for storing Minimizer option, with static default values that can be 
	changed by the user

  FitConfig: 
   	- use default values from MinimizerOption class
   	- rename method to create parameter settings from a function

  FitUtil.cxx:   
    	improve the derivative calculations used in the effective chi2 and in Fumili and 
	fix a bug for evaluation of likelihood or chi2 terms. 
	In  EvaluatePdf() work and return  the log of the pdf. 
      
  FitResult:
	- improve the class by adding extra information like, num. of free parameters, 
	minimizer status, global correlation coefficients, information about fixed 
	and bound parameters. 
   	- add method for getting fit confidence intervals 
  	- improve print method   

  DataRange: 
	add method SetRange to distinguish from AddRange. SetRange deletes the existing 
	ranges. 

  ParamsSettings: make few methods const

  FCN functions (Chi2FCN, LogLikelihoodFCN, etc..) 
	move some common methods and data members in base class (FitMethodFunction)

  RootFinder: add template Solve() for any callable function.  

mathmore:
--------
  minimizer classes: fill status information
  GSLNLSMinimizer: return error and covariance matrix 

minuit2: 
-------
  Minuit2Minimizer: fill  status information 
  DavidonErrorUpdator: check that delgam or gvg are not zero ( can happen when dg = 0)
  FumiliFCNAdapter: work on the log of pdf

minuit:
------- 
  TLinearMinimizer: add support for robust fitting
  TMinuitMinimizer: fill status information and fix a bug in filling the correlation matrix. 
 fumili:
 ------ 
  add TFumiliMinimizer: 
	wrapper class for TFumili using Minimizer interface

// @(#)root/mathcore:$Id$
// Author: L. Moneta Fri Aug 17 14:29:24 2007

/**********************************************************************
 *                                                                    *
 * Copyright (c) 2007  LCG ROOT Math Team, CERN/PH-SFT                *
 *                                                                    *
 *                                                                    *
 **********************************************************************/

// Header file for class LogLikelihoodFCN

#ifndef ROOT_Fit_LogLikelihoodFCN
#define ROOT_Fit_LogLikelihoodFCN

#ifndef ROOT_Math_FitMethodFunction
#include "Math/FitMethodFunction.h"
#endif

#ifndef ROOT_Math_IParamFunction
#include "Math/IParamFunction.h"
#endif

#ifndef ROOT_Fit_UnBinData
#include "Fit/UnBinData.h"
#endif

#ifndef ROOT_Fit_FitUtil
#include "Fit/FitUtil.h"
#endif
//#define PARALLEL
#ifdef PARALLEL
#ifndef ROOT_Fit_FitUtilParallel
#include "Fit/FitUtilParallel.h"
#endif
#endif

namespace ROOT { 

   namespace Fit { 


//___________________________________________________________________________________
/** 
   LogLikelihoodFCN class 
   for likelihood fits 

   it is template to distinguish gradient and non-gradient case

   @ingroup  FitMethodFunc   
*/ 
template<class FunType> 
class LogLikelihoodFCN : public ::ROOT::Math::BasicFitMethodFunction<FunType>  {

public: 



   typedef  ::ROOT::Math::BasicFitMethodFunction<FunType> BaseObjFunction; 
   typedef typename  BaseObjFunction::BaseFunction BaseFunction; 

   typedef  ::ROOT::Math::IParamMultiFunction IModelFunction;


   /** 
      Constructor from unbin data set and model function (pdf)
   */ 
   LogLikelihoodFCN (const UnBinData & data, IModelFunction & func) : 
      BaseObjFunction(func.NPar(), data.Size() ),
      fData(data), 
      fFunc(func), 
      fNEffPoints(0),
      fGrad ( std::vector<double> ( func.NPar() ) )
   {}
  

   /** 
      Destructor (no operations)
   */ 
   virtual ~LogLikelihoodFCN () {}

private:
   // usually copying is non trivial, so we make this unaccessible

   /** 
      Dummy Copy constructor (private)
   */ 
   LogLikelihoodFCN(const LogLikelihoodFCN &) {} 

   /** 
      Dummy Assignment operator (private)
   */ 
   LogLikelihoodFCN & operator = (const LogLikelihoodFCN & rhs) { 
      return *this;
   } 

public: 

   /// clone the function (need to return Base for Windows)
   BaseFunction * Clone() const { return  new LogLikelihoodFCN(fData,fFunc); }


   //using BaseObjFunction::operator();

   // effective points used in the fit
   unsigned int NFitPoints() const { return fNEffPoints; }

   /// i-th likelihood contribution and its gradient
   double DataElement(const double * x, unsigned int i, double * g) const { 
      return FitUtil::EvaluatePdf(fFunc, fData, x, i, g); 
   }


   // need to be virtual to be instantited
   virtual void Gradient(const double *x, double *g) const { 
      // evaluate the chi2 gradient
      FitUtil::EvaluateLogLGradient(fFunc, fData, x, g, fNEffPoints);
   }

   /// get type of fit method function
   virtual  typename BaseObjFunction::Type GetType() const { return BaseObjFunction::kLogLikelihood; }

   /// access to const reference to the data 
   virtual const UnBinData & Data() const { return fData; }

   /// access to const reference to the model function
   virtual const IModelFunction & ModelFunction() const { return fFunc; }

protected: 


private:

   /**
      Evaluation of the  function (required by interface)
    */
   double DoEval (const double * x) const { 
      this->UpdateNCalls();
#ifdef PARALLEL
      return FitUtilParallel::EvaluateLogL(fFunc, fData, x, fNEffPoints); 
#else 
      return FitUtil::EvaluateLogL(fFunc, fData, x, fNEffPoints); 
#endif
   } 

   // for derivatives 
   virtual double  DoDerivative(const double * x, unsigned int icoord ) const { 
      Gradient(x, &fGrad[0]); 
      return fGrad[icoord]; 
   }

 
      //data member

   const UnBinData & fData; 
   mutable IModelFunction & fFunc; 

   mutable unsigned int fNEffPoints;  // number of effective points used in the fit 

   mutable std::vector<double> fGrad; // for derivatives


}; 

   } // end namespace Fit

} // end namespace ROOT


#endif /* ROOT_Fit_LogLikelihoodFCN */

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