Gabriele Cosmo
112 lines
4.8 KiB
C++
112 lines
4.8 KiB
C++
//
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// ********************************************************************
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// * DISCLAIMER *
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// * *
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// * The following disclaimer summarizes all the specific disclaimers *
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// * of contributors to this software. The specific disclaimers,which *
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// * govern, are listed with their locations in: *
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// * http://cern.ch/geant4/license *
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// * *
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// * Neither the authors of this software system, nor their employing *
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// * institutes,nor the agencies providing financial support for this *
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// * work make any representation or warranty, express or implied, *
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// * regarding this software system or assume any liability for its *
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// * use. *
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// * *
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// * This code implementation is the intellectual property of the *
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// * GEANT4 collaboration. *
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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 *
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// * statement, and all its terms. *
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// ********************************************************************
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//
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//
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// $Id: G4GaussLegendreQ.hh,v 1.4 2001/07/11 10:00:39 gunter Exp $
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// GEANT4 tag $Name: geant4-05-00 $
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//
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// Class description:
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//
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// Class for Gauss-Legendre integration method
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// Roots of ortogonal polynoms and corresponding weights are calculated based on
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// iteration method (by bisection Newton algorithm). Constant values for initial
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// approximations were derived from the book: M. Abramowitz, I. Stegun, Handbook
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// of mathematical functions, DOVER Publications INC, New York 1965 ; chapters 9,
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// 10, and 22 .
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//
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// ------------------------- CONSTRUCTORS: -------------------------------
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//
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// Constructor for GaussLegendre quadrature method. The value nLegendre set the
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// accuracy required, i.e the number of points where the function pFunction will
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// be evaluated during integration. The constructor creates the arrays for
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// abscissas and weights that used in Gauss-Legendre quadrature method.
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// The values a and b are the limits of integration of the pFunction.
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//
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// G4GaussLegendreQ( function pFunction,
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// G4int nLegendre )
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//
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// -------------------------- METHODS: ---------------------------------------
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//
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// Returns the integral of the function to be pointed by fFunction between a and b,
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// by 2*fNumber point Gauss-Legendre integration: the function is evaluated exactly
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// 2*fNumber Times at interior points in the range of integration. Since the weights
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// and abscissas are, in this case, symmetric around the midpoint of the range of
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// integration, there are actually only fNumber distinct values of each.
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//
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// G4double Integral(G4double a, G4double b) const
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//
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// -----------------------------------------------------------------------
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//
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// Returns the integral of the function to be pointed by fFunction between a and b,
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// by ten point Gauss-Legendre integration: the function is evaluated exactly
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// ten Times at interior points in the range of integration. Since the weights
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// and abscissas are, in this case, symmetric around the midpoint of the range of
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// integration, there are actually only five distinct values of each
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//
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// G4double
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// QuickIntegral(G4double a, G4double b) const
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//
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// ---------------------------------------------------------------------
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//
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// Returns the integral of the function to be pointed by fFunction between a and b,
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// by 96 point Gauss-Legendre integration: the function is evaluated exactly
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// ten Times at interior points in the range of integration. Since the weights
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// and abscissas are, in this case, symmetric around the midpoint of the range of
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// integration, there are actually only five distinct values of each
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//
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// G4double
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// AccurateIntegral(G4double a, G4double b) const
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// ------------------------------- HISTORY --------------------------------
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//
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// 13.05.97 V.Grichine (Vladimir.Grichine@cern.chz0
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#ifndef G4GAUSSLEGENDREQ_HH
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#define G4GAUSSLEGENDREQ_HH
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#include "G4VGaussianQuadrature.hh"
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class G4GaussLegendreQ : public G4VGaussianQuadrature
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{
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public:
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G4GaussLegendreQ( function pFunction ) ;
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G4GaussLegendreQ( function pFunction,
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G4int nLegendre ) ;
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// Methods
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G4double Integral(G4double a, G4double b) const ;
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G4double QuickIntegral(G4double a, G4double b) const ;
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G4double AccurateIntegral(G4double a, G4double b) const ;
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private:
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G4GaussLegendreQ(const G4GaussLegendreQ&);
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G4GaussLegendreQ& operator=(const G4GaussLegendreQ&);
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};
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#endif
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