// // ******************************************************************** // * 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. * // ******************************************************************** // // G4GaussLegendreQ // // Class description: // // Class for Gauss-Legendre integration 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. // Author: V.Grichine, 13.05.1997 // -------------------------------------------------------------------- #ifndef G4GAUSSLEGENDREQ_HH #define G4GAUSSLEGENDREQ_HH 1 #include "G4VGaussianQuadrature.hh" class G4GaussLegendreQ : public G4VGaussianQuadrature { public: explicit G4GaussLegendreQ(function pFunction); G4GaussLegendreQ(function pFunction, G4int nLegendre); // Constructor for GaussLegendre quadrature method. The value nLegendre set // the accuracy required, i.e the number of points where the function // pFunction will be evaluated during integration. The constructor creates // the arrays for abscissas and weights that used in Gauss-Legendre // quadrature method. // The values a and b are the limits of integration of the pFunction. G4GaussLegendreQ(const G4GaussLegendreQ&) = delete; G4GaussLegendreQ& operator=(const G4GaussLegendreQ&) = delete; G4double Integral(G4double a, G4double b) const; // Returns the integral of the function to be pointed by fFunction between a // and b, by 2*fNumber point Gauss-Legendre integration: the function is // evaluated exactly 2*fNumber Times at interior points in the range of // integration. Since the weights and abscissas are, in this case, symmetric // around the midpoint of the range of integration, there are actually only // fNumber distinct values of each. G4double QuickIntegral(G4double a, G4double b) const; // Returns the integral of the function to be pointed by fFunction between a // and b, by ten point Gauss-Legendre integration: the function is evaluated // exactly ten Times at interior points in the range of integration. Since // the weights and abscissas are, in this case, symmetric around the midpoint // of the range of integration, there are actually only five distinct values // of each. G4double AccurateIntegral(G4double a, G4double b) const; // Returns the integral of the function to be pointed by fFunction between a // and b, by 96 point Gauss-Legendre integration: the function is evaluated // exactly ten Times at interior points in the range of integration. Since // the weights and abscissas are, in this case, symmetric around the midpoint // of the range of integration, there are actually only five distinct values // of each. }; #endif