RootFinder.cxx

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// @(#)root/mathcore:$Id$
// Authors: David Gonzalez Maline    01/2008
 
 /**********************************************************************
  *                                                                    *
  * Copyright (c) 2006  CERN                                           *
  * All rights reserved.                                               *
  *                                                                    *
  * For the licensing terms see $ROOTSYS/LICENSE.                      *
  * For the list of contributors see $ROOTSYS/README/CREDITS.          *
  *                                                                    *
  **********************************************************************/
 
#include "Math/RootFinder.h"
#include "Math/IRootFinderMethod.h"
#include "Math/BrentRootFinder.h"
#include "Math/ModABRootFinder.h"
 
#include "RConfigure.h"
 
#ifndef MATH_NO_PLUGIN_MANAGER
 
#include "TROOT.h"
#include "TPluginManager.h"
 
#else // case no plugin manager is available
#ifdef R__HAS_MATHMORE
#include "Math/RootFinderAlgorithms.h"
#endif
 
#endif
 
#include <cassert>
 
#include "Math/Error.h"
 
namespace ROOT {
namespace Math {
 
 
RootFinder::RootFinder(RootFinder::EType type) :
   fSolver(nullptr)
{
   // constructor passing type (default is kBRENT)
   const bool success = SetMethod(type);
   if (!success)
      throw std::runtime_error("ROOT::Math::RootFinder: ROOT was built without the requested algorithm");
}
 
bool RootFinder::SetMethod(RootFinder::EType type)
{
   fSolver = nullptr;
 
   // set method - Use the plug-in manager if method is implemented in MathMore
   if ( type == RootFinder::kBRENT )
   {
      fSolver = new BrentRootFinder();
      return true;
   }
 
   if (type == RootFinder::kMODAB) 
   {
      fSolver = new ModABRootFinder();
      return true;
   }
 
#ifdef MATH_NO_PLUGIN_MANAGER    // no PM available
#ifdef R__HAS_MATHMORE
 
   switch(type) {
 
   case kGSL_BISECTION:
      fSolver = new ROOT::Math::Roots::Bisection();
      break;
   case kGSL_FALSE_POS:
      fSolver = new ROOT::Math::Roots::FalsePos();
      break;
   case kGSL_BRENT:
      fSolver = new ROOT::Math::Roots::Brent();
      break;
   case kGSL_NEWTON:
      fSolver = new ROOT::Math::Roots::Newton();
      break;
   case kGSL_SECANT:
      fSolver = new ROOT::Math::Roots::Secant();
      break;
   case kGSL_STEFFENSON:
      fSolver = new ROOT::Math::Roots::Steffenson();
      break;
   default:
      MATH_ERROR_MSG("RootFinder::SetMethod","RootFinderMethod type is not available in MathCore");
      fSolver = 0;
      return false;
      break;
   };
 
#else
   MATH_ERROR_MSG("RootFinder::SetMethod","RootFinderMethod type is not available in MathCore");
   return false;
#endif
 
#else  // case of using Plugin Manager
   TPluginHandler *h;
   std::string stype;
 
   switch(type) {
 
   case kGSL_BISECTION:
      stype = "Bisection";
      break;
   case kGSL_FALSE_POS:
      stype = "FalsePos";
      break;
   case kGSL_BRENT:
      stype = "Brent";
      break;
   case kGSL_NEWTON:
      stype = "Newton";
      break;
   case kGSL_SECANT:
      stype = "Secant";
      break;
   case kGSL_STEFFENSON:
      stype = "Steffenson";
      break;
   default:
      MATH_ERROR_MSG("RootFinder::SetMethod","RootFinderMethod type is not available in MathCore");
      fSolver = nullptr;
      return false;
      break;
   };
 
   if ((h = gROOT->GetPluginManager()->FindHandler("ROOT::Math::IRootFinderMethod", stype.c_str() ))) {
      if (h->LoadPlugin() == -1) {
         MATH_ERROR_MSG("RootFinder::SetMethod","Error loading RootFinderMethod");
         return false;
      }
 
      fSolver = reinterpret_cast<ROOT::Math::IRootFinderMethod *>(h->ExecPlugin(0));
   }
 
#endif
 
   if (!fSolver) {
      MATH_ERROR_MSG("RootFinder::SetMethod","Error loading RootFinderMethod");
      return false;
   }
 
   return true;
}
 
 
RootFinder::~RootFinder()
{
   // destructor
   delete fSolver;
}
 
 
}
}