// // ******************************************************************** // * License and Disclaimer * // * * // * The Geant4 software is copyright of the Copyright Holders of * // * the Geant4 Collaboration. It is provided under the terms and * // * conditions of the Geant4 Software License, included in the file * // * LICENSE and available at http://cern.ch/geant4/license . These * // * include a list of copyright holders. * // * * // * 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. Please see the license in the file LICENSE and URL above * // * for the full disclaimer and the limitation of liability. * // * * // * This code implementation is the result of the scientific and * // * technical work of the GEANT4 collaboration. * // * By using, copying, modifying or distributing the software (or * // * any work based on the software) you agree to acknowledge its * // * use in resulting scientific publications, and indicate your * // * acceptance of all terms of the Geant4 Software license. * // ******************************************************************** // // // $Id: G4GaussLaguerreQ.hh,v 1.6 2006/06/29 18:59:40 gunter Exp $ // GEANT4 tag $Name: geant4-09-03 $ // // 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