Files
geant4/source/global/HEPNumerics/include/G4SimpleIntegration.hh
T
2016-06-09 10:15:15 +02:00

113 lines
4.3 KiB
C++

//
// ********************************************************************
// * DISCLAIMER *
// * *
// * The following disclaimer summarizes all the specific disclaimers *
// * of contributors to this software. The specific disclaimers,which *
// * govern, are listed with their locations in: *
// * http://cern.ch/geant4/license *
// * *
// * 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. *
// * *
// * This code implementation is the intellectual property of the *
// * GEANT4 collaboration. *
// * By copying, distributing or modifying the Program (or any work *
// * based on the Program) you indicate your acceptance of this *
// * statement, and all its terms. *
// ********************************************************************
//
//
// $Id: G4SimpleIntegration.hh,v 1.3 2001/07/11 10:00:40 gunter Exp $
// GEANT4 tag $Name: geant4-05-01 $
//
// Class description:
//
// Class for realisation of simple numerical methodes for integration of functions
// with signature: double f(double). The methods based mainly on algorithms given in
// the book : An introduction to NUMERICAL METHODS IN C++, B.H. Flowers, Claredon
// Press, Oxford, 1995
//
// --------------------------- Member data: -------------------------------------
//
// fFunction - pointer to the function to be integrated
// fTolerance - accuracy of integration in Adaptive Gauss method
// fMaxDepth = 100 - constant maximum iteration depth for
// Adaptive Gauss method
//
// --------------------------- Methods: -----------------------------------------
//
// Trapezoidal, MidPoint, Gauss,
// and Simpson(double a,double b,int n) - integrate function pointed
// by fFunction from a to b by n iterations, i.e. with Step (b-a)/n
// according to the correspondent method
//
// AdaptGausIntegration(double a, double b) - integrate function from a to be with
// accuracy <= fTolerance
// ----------------------------- History: ----------------------------------------
//
// 26.03.97 V.Grichine ( Vladimir.Grichine@cern.ch )
#ifndef G4SIMPLEINTEGRATION_HH
#define G4SIMPLEINTEGRATION_HH
#include "globals.hh"
typedef G4double (*function)(G4double) ;
class G4SimpleIntegration
{
public:
G4SimpleIntegration( function pFunction ) ;
G4SimpleIntegration( function pFunction,
G4double pTolerance ) ;
~G4SimpleIntegration() ;
// Simple integration methods
G4double Trapezoidal(G4double xInitial,
G4double xFinal,
G4int iterationNumber ) ;
G4double MidPoint(G4double xInitial,
G4double xFinal,
G4int iterationNumber ) ;
G4double Gauss(G4double xInitial,
G4double xFinal,
G4int iterationNumber ) ;
G4double Simpson(G4double xInitial,
G4double xFinal,
G4int iterationNumber ) ;
// Adaptive Gauss integration with accuracy ~ fTolerance
G4double AdaptGaussIntegration( G4double xInitial,
G4double xFinal ) ;
protected:
G4double Gauss( G4double xInitial,
G4double xFinal ) ;
void AdaptGauss( G4double xInitial,
G4double xFinal,
G4double& sum,
G4int& depth ) ;
private:
function fFunction ;
G4double fTolerance ;
static G4int fMaxDepth ;
} ;
#endif