Geant4 Cross Reference

Cross-Referencing   Geant4
Geant4/global/HEPNumerics/src/G4GaussChebyshevQ.cc

Version: [ ReleaseNotes ] [ 1.0 ] [ 1.1 ] [ 2.0 ] [ 3.0 ] [ 3.1 ] [ 3.2 ] [ 4.0 ] [ 4.0.p1 ] [ 4.0.p2 ] [ 4.1 ] [ 4.1.p1 ] [ 5.0 ] [ 5.0.p1 ] [ 5.1 ] [ 5.1.p1 ] [ 5.2 ] [ 5.2.p1 ] [ 5.2.p2 ] [ 6.0 ] [ 6.0.p1 ] [ 6.1 ] [ 6.2 ] [ 6.2.p1 ] [ 6.2.p2 ] [ 7.0 ] [ 7.0.p1 ] [ 7.1 ] [ 7.1.p1 ] [ 8.0 ] [ 8.0.p1 ] [ 8.1 ] [ 8.1.p1 ] [ 8.1.p2 ] [ 8.2 ] [ 8.2.p1 ] [ 8.3 ] [ 8.3.p1 ] [ 8.3.p2 ] [ 9.0 ] [ 9.0.p1 ] [ 9.0.p2 ] [ 9.1 ] [ 9.1.p1 ] [ 9.1.p2 ] [ 9.1.p3 ] [ 9.2 ] [ 9.2.p1 ] [ 9.2.p2 ] [ 9.2.p3 ] [ 9.2.p4 ] [ 9.3 ] [ 9.3.p1 ] [ 9.3.p2 ] [ 9.4 ] [ 9.4.p1 ] [ 9.4.p2 ] [ 9.4.p3 ] [ 9.4.p4 ] [ 9.5 ] [ 9.5.p1 ] [ 9.5.p2 ] [ 9.6 ] [ 9.6.p1 ] [ 9.6.p2 ] [ 9.6.p3 ] [ 9.6.p4 ] [ 10.0 ] [ 10.0.p1 ] [ 10.0.p2 ] [ 10.0.p3 ] [ 10.0.p4 ] [ 10.1 ] [ 10.1.p1 ] [ 10.1.p2 ] [ 10.1.p3 ] [ 10.2 ] [ 10.2.p1 ] [ 10.2.p2 ] [ 10.2.p3 ] [ 10.3 ] [ 10.3.p1 ] [ 10.3.p2 ] [ 10.3.p3 ] [ 10.4 ] [ 10.4.p1 ] [ 10.4.p2 ] [ 10.4.p3 ] [ 10.5 ] [ 10.5.p1 ] [ 10.6 ] [ 10.6.p1 ] [ 10.6.p2 ] [ 10.6.p3 ] [ 10.7 ] [ 10.7.p1 ] [ 10.7.p2 ] [ 10.7.p3 ] [ 10.7.p4 ] [ 11.0 ] [ 11.0.p1 ] [ 11.0.p2 ] [ 11.0.p3, ] [ 11.0.p4 ] [ 11.1 ] [ 11.1.1 ] [ 11.1.2 ] [ 11.1.3 ] [ 11.2 ] [ 11.2.1 ] [ 11.2.2 ] [ 11.3.0 ] 

  1 //
  2 // ********************************************************************
  3 // * License and Disclaimer                                           *
  4 // *                                                                  *
  5 // * The  Geant4 software  is  copyright of the Copyright Holders  of *
  6 // * the Geant4 Collaboration.  It is provided  under  the terms  and *
  7 // * conditions of the Geant4 Software License,  included in the file *
  8 // * LICENSE and available at  http://cern.ch/geant4/license .  These *
  9 // * include a list of copyright holders.                             *
 10 // *                                                                  *
 11 // * Neither the authors of this software system, nor their employing *
 12 // * institutes,nor the agencies providing financial support for this *
 13 // * work  make  any representation or  warranty, express or implied, *
 14 // * regarding  this  software system or assume any liability for its *
 15 // * use.  Please see the license in the file  LICENSE  and URL above *
 16 // * for the full disclaimer and the limitation of liability.         *
 17 // *                                                                  *
 18 // * This  code  implementation is the result of  the  scientific and *
 19 // * technical work of the GEANT4 collaboration.                      *
 20 // * By using,  copying,  modifying or  distributing the software (or *
 21 // * any work based  on the software)  you  agree  to acknowledge its *
 22 // * use  in  resulting  scientific  publications,  and indicate your *
 23 // * acceptance of all terms of the Geant4 Software license.          *
 24 // ********************************************************************
 25 //
 26 // G4GaussChebyshevQ class implementation
 27 //
 28 // Author: V.Grichine, 13.05.1997
 29 // --------------------------------------------------------------------
 30 
 31 #include "G4GaussChebyshevQ.hh"
 32 #include "G4PhysicalConstants.hh"
 33 
 34 // -----------------------------------------------------
 35 //
 36 // Constructor for Gauss-Chebyshev quadrature method
 37 //
 38 G4GaussChebyshevQ::G4GaussChebyshevQ(function pFunction, G4int nChebyshev)
 39   : G4VGaussianQuadrature(pFunction)
 40 {
 41   fNumber      = nChebyshev;  // Try to reduce fNumber twice ??
 42   G4double cof = pi / fNumber;
 43   fAbscissa    = new G4double[fNumber];
 44   fWeight      = new G4double[fNumber];
 45   for(G4int i = 0; i < fNumber; ++i)
 46   {
 47     fAbscissa[i] = std::cos(cof * (i + 0.5));
 48     fWeight[i]   = cof * std::sqrt(1 - fAbscissa[i] * fAbscissa[i]);
 49   }
 50 }
 51 
 52 // -------------------------------------------------------------------------------
 53 //
 54 // Integrates function pointed by fFunction from a to b by Gauss-Chebyshev
 55 // quadrature method
 56 //
 57 G4double G4GaussChebyshevQ::Integral(G4double a, G4double b) const
 58 {
 59   G4double xDiff = 0.5 * (b - a), xMean = 0.5 * (a + b), dx = 0.0,
 60            integral = 0.0;
 61 
 62   for(G4int i = 0; i < fNumber; ++i)
 63   {
 64     dx = xDiff * fAbscissa[i];
 65     integral += fWeight[i] * fFunction(xMean + dx);
 66   }
 67   return integral *= xDiff;
 68 }
 69