G4GaussLaguerreQ.hh

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//
// $Id$
//
// Class description:
//
// Class for realization of Gauss-Laguerre quadrature method
// Roots of ortogonal polynoms and corresponding weights are calculated based on
// iteration method (by bisection Newton algorithm). Constant values for initial
// approximations were derived from the book: M. Abramowitz, I. Stegun, Handbook
// of mathematical functions, DOVER Publications INC, New York 1965 ; chapters 9,
// 10, and 22 .
//
// ---------------------------------------------------------------------------
//
// Constructor for Gauss-Laguerre quadrature method: integral from zero to
// infinity of std::pow(x,alpha)*std::exp(-x)*f(x). The value of nLaguerre sets the accuracy.
// The constructor creates arrays fAbscissa[0,..,nLaguerre-1] and 
// fWeight[0,..,nLaguerre-1] . The function GaussLaguerre(f) should be called
// then with any f .
//
// G4GaussLaguerreQ( function pFunction,
//                   G4double alpha,
//           G4int nLaguerre  ) 
//
//
// -------------------------------------------------------------------------
//
// Gauss-Laguerre method for integration of std::pow(x,alpha)*std::exp(-x)*pFunction(x)
// from zero up to infinity. pFunction is evaluated in fNumber points for which
// fAbscissa[i] and fWeight[i] arrays were created in constructor
//
// G4double  Integral() const 
 
// ------------------------------- HISTORY --------------------------------
//
// 13.05.97 V.Grichine (Vladimir.Grichine@cern.chz0
 
#ifndef G4GAUSSLAGUERREQ_HH
#define G4GAUSSLAGUERREQ_HH
 
#include "G4VGaussianQuadrature.hh"
 
class G4GaussLaguerreQ : public G4VGaussianQuadrature
{
public:
        G4GaussLaguerreQ( function pFunction,
                      G4double alpha,
              G4int nLaguerre           ) ;
                   
        // Methods
                 
        G4double Integral() const ;
 
private:
 
    G4GaussLaguerreQ(const G4GaussLaguerreQ&);
    G4GaussLaguerreQ& operator=(const G4GaussLaguerreQ&);
};
 
#endif