G4LinLogLogInterpolation.cc

Go to the documentation of this file.

//
// ********************************************************************
// * License and Disclaimer                                           *
// *                                                                  *
// * The  Geant4 software  is  copyright of the Copyright Holders  of *
// * the Geant4 Collaboration.  It is provided  under  the terms  and *
// * conditions of the Geant4 Software License,  included in the file *
// * LICENSE and available at  http://cern.ch/geant4/license .  These *
// * include a list of copyright holders.                             *
// *                                                                  *
// * Neither the authors of this software system, nor their employing *
// * institutes,nor the agencies providing financial support for this *
// * work  make  any representation or  warranty, express or implied, *
// * regarding  this  software system or assume any liability for its *
// * use.  Please see the license in the file  LICENSE  and URL above *
// * for the full disclaimer and the limitation of liability.         *
// *                                                                  *
// * This  code  implementation is the result of  the  scientific and *
// * technical work of the GEANT4 collaboration.                      *
// * By using,  copying,  modifying or  distributing the software (or *
// * any work based  on the software)  you  agree  to acknowledge its *
// * use  in  resulting  scientific  publications,  and indicate your *
// * acceptance of all terms of the Geant4 Software license.          *
// ********************************************************************
//
//
// Author:  Vladimir Ivanchenko ([email protected])
//
// History:
// -----------
// 29 May 2002   VI        Created
//
// -------------------------------------------------------------------
 
#include "G4LinLogLogInterpolation.hh"
 
// Constructor
 
G4LinLogLogInterpolation::G4LinLogLogInterpolation()
{ }
 
// Destructor
 
G4LinLogLogInterpolation::~G4LinLogLogInterpolation()
{ }
 
G4VDataSetAlgorithm* G4LinLogLogInterpolation::Clone() const 
{ return new G4LinLogLogInterpolation; }
 
 
G4double G4LinLogLogInterpolation::Calculate(G4double x, G4int bin, 
                      const G4DataVector& points, 
                      const G4DataVector& data) const
{
  //G4cout << "G4LinLogLogInterpolation is performed (2 arguments) " << G4endl;
  G4int nBins = G4int(data.size() - 1);
  G4double value = 0.;
  if (x < points[0])
    {
      value = 0.;
    }
  else if (bin < nBins)
    {
      G4double e1 = points[bin];
      G4double e2 = points[bin+1];
      G4double d1 = data[bin];
      G4double d2 = data[bin+1];
      if(d1 > 0.0 && d2 > 0.0) {
        value = (std::log10(d1)*std::log10(e2/x) + std::log10(d2)*std::log10(x/e1)) / std::log10(e2/e1);
        value = std::pow(10.,value);
      } else {
        value = (d1*std::log10(e2/x) + d2*std::log10(x/e1)) / std::log10(e2/e1);
      }
    }
  else
    {
      value = data[nBins];
    }
 
  return value;
}
 
G4double G4LinLogLogInterpolation::Calculate(G4double x, G4int bin, 
                      const G4DataVector& points,
                                          const G4DataVector& data,
                                          const G4DataVector& log_points, 
                      const G4DataVector& log_data) const
{
  //G4cout << "G4LinLogLogInterpolation is performed(4 arguments)  " << G4endl;
  G4int nBins = G4int(data.size() - 1);
  G4double value = 0.;
  G4double log_x = std::log10(x);
  if (x < points[0])
    {
      value = 0.;
    }
  else if (bin < nBins)
    {
      G4double e1 = points[bin];
      G4double e2 = points[bin+1];
      G4double d1 = data[bin];
      G4double d2 = data[bin+1];      
      G4double log_e1 = log_points[bin];
      G4double log_e2 = log_points[bin+1];
      G4double log_d1 = log_data[bin];
      G4double log_d2 = log_data[bin+1];
      //G4cout << "x = " << x << " , log_x = " << log_x << " , bin = " << bin << G4endl;
      //G4cout << "e1 = " << e1 << " , d1 = " << d1 << G4endl;
      //G4cout << "e2 = " << e2 << " , d2 = " << d2 << G4endl;
      //G4cout << "log_e1 = " << log_e1 << " , log_d1 = " << log_d1 << G4endl;
      //G4cout << "log_e2 = " << log_e2 << " , log_d2 = " << log_d2 <<G4endl;
      if (d1 > 0.0 && d2 > 0.0)
       {
         // Values e1, e2, d1 and d2 are the log values of the corresponding
         // original energy and data values. Simple linear interpolation performed
         // on loagarithmic data should be equivalent to log-log interpolation
         value = log_d1 + (log_d2 - log_d1)*(log_x - log_e1)/(log_e2 - log_e1);
 
         //G4cout << "Case of normal log-log interpolation" << G4endl;
         //G4cout << "Temp log interpolated value: log_value = " << value << G4endl;
 
         // Delogarithmize to obtain interpolated value
         value = std::pow(10.,value);
 
         //G4cout << "Final Interpolated value: " << value << G4endl << G4endl;
       }
     else
       {
        // Case of semi log-log interpolation
        //G4cout << "G4LinLogLogInterpolation - Case of SemiLogInterpolation" << G4endl;
        if (e1 == 0.0) e1 = 1e-300;
        if (e2 == 0.0) e2 = 1e-300;
        value = d1 + (d2 - d1)*(log_x - log_e1)/(log_e2 - log_e1);
        //G4cout << "LinLogInterpolation: Final Interpolated value: " << value << G4endl << G4endl;
       }
    }
  else
    {
      value = data[nBins];
    }
  return value;
}