Gabriele Cosmo
84 lines
3.4 KiB
C++
84 lines
3.4 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: G4GaussLaguerreQ.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 realization of Gauss-Laguerre quadrature 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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// ---------------------------------------------------------------------------
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//
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// Constructor for Gauss-Laguerre quadrature method: integral from zero to
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// infinity of pow(x,alpha)*exp(-x)*f(x). The value of nLaguerre sets the accuracy.
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// The constructor creates arrays fAbscissa[0,..,nLaguerre-1] and
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// fWeight[0,..,nLaguerre-1] . The function GaussLaguerre(f) should be called
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// then with any f .
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//
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// G4GaussLaguerreQ( function pFunction,
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// G4double alpha,
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// G4int nLaguerre )
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//
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//
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// -------------------------------------------------------------------------
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//
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// Gauss-Laguerre method for integration of pow(x,alpha)*exp(-x)*pFunction(x)
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// from zero up to infinity. pFunction is evaluated in fNumber points for which
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// fAbscissa[i] and fWeight[i] arrays were created in constructor
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//
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// G4double Integral() 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 G4GAUSSLAGUERREQ_HH
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#define G4GAUSSLAGUERREQ_HH
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#include "G4VGaussianQuadrature.hh"
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class G4GaussLaguerreQ : public G4VGaussianQuadrature
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{
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public:
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G4GaussLaguerreQ( function pFunction,
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G4double alpha,
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G4int nLaguerre ) ;
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// Methods
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G4double Integral() const ;
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private:
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G4GaussLaguerreQ(const G4GaussLaguerreQ&);
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G4GaussLaguerreQ& operator=(const G4GaussLaguerreQ&);
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};
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#endif
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