Gabriele Cosmo
97 lines
3.1 KiB
C++
97 lines
3.1 KiB
C++
// This code implementation is the intellectual property of
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// the GEANT4 collaboration.
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//
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// By copying, distributing or modifying the Program (or any work
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// based on the Program) you indicate your acceptance of this statement,
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// and all its terms.
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//
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// $Id: G4SimpleIntegration.hh,v 1.2 1999/11/16 17:30:59 gcosmo Exp $
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// GEANT4 tag $Name: geant4-01-00 $
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//
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// Class description:
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//
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// Class for realisation of simple numerical methodes for integration of functions
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// with signature: double f(double). The methods based mainly on algorithms given in
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// the book : An introduction to NUMERICAL METHODS IN C++, B.H. Flowers, Claredon
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// Press, Oxford, 1995
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//
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// --------------------------- Member data: -------------------------------------
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//
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// fFunction - pointer to the function to be integrated
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// fTolerance - accuracy of integration in Adaptive Gauss method
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// fMaxDepth = 100 - constant maximum iteration depth for
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// Adaptive Gauss method
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//
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// --------------------------- Methods: -----------------------------------------
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//
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// Trapezoidal, MidPoint, Gauss,
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// and Simpson(double a,double b,int n) - integrate function pointed
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// by fFunction from a to b by n iterations, i.e. with Step (b-a)/n
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// according to the correspondent method
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//
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// AdaptGausIntegration(double a, double b) - integrate function from a to be with
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// accuracy <= fTolerance
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// ----------------------------- History: ----------------------------------------
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//
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// 26.03.97 V.Grichine ( Vladimir.Grichine@cern.ch )
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#ifndef G4SIMPLEINTEGRATION_HH
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#define G4SIMPLEINTEGRATION_HH
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#include "globals.hh"
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typedef G4double (*function)(G4double) ;
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class G4SimpleIntegration
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{
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public:
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G4SimpleIntegration( function pFunction ) ;
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G4SimpleIntegration( function pFunction,
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G4double pTolerance ) ;
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~G4SimpleIntegration() ;
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// Simple integration methods
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G4double Trapezoidal(G4double xInitial,
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G4double xFinal,
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G4int iterationNumber ) ;
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G4double MidPoint(G4double xInitial,
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G4double xFinal,
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G4int iterationNumber ) ;
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G4double Gauss(G4double xInitial,
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G4double xFinal,
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G4int iterationNumber ) ;
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G4double Simpson(G4double xInitial,
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G4double xFinal,
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G4int iterationNumber ) ;
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// Adaptive Gauss integration with accuracy ~ fTolerance
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G4double AdaptGaussIntegration( G4double xInitial,
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G4double xFinal ) ;
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protected:
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G4double Gauss( G4double xInitial,
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G4double xFinal ) ;
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void AdaptGauss( G4double xInitial,
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G4double xFinal,
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G4double& sum,
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G4int& depth ) ;
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private:
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function fFunction ;
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G4double fTolerance ;
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static G4int fMaxDepth ;
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} ;
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#endif
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