// Copyright (c) 2005 Stanford University (USA). // All rights reserved. // // This file is part of CGAL (www.cgal.org); you can redistribute it and/or // modify it under the terms of the GNU Lesser General Public License as // published by the Free Software Foundation; either version 3 of the License, // or (at your option) any later version. // // Licensees holding a valid commercial license may use this file in // accordance with the commercial license agreement provided with the software. // // This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE // WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. // // $URL$ // $Id$ // // // Author(s) : Daniel Russel #ifndef CGAL_POLYNOMIAL_INTERNAL_SHIFT_POWER_H #define CGAL_POLYNOMIAL_INTERNAL_SHIFT_POWER_H #include namespace CGAL { namespace POLYNOMIAL { namespace internal { //------------------------------------------------------------------ template class Shift_power { public: typedef typename Polynomial::NT NT; typedef unsigned int argument_type; typedef Polynomial result_type; Shift_power(){} Shift_power(unsigned int p): p(p){} void write(std::ostream &out) const { out << "shift_power"; } Polynomial operator()(const Polynomial& f) const { #if 0 // this is the old buggy code: the for-loop below was accessing // an array element which was out of the array bounds int deg = f.degree(); unsigned int sdeg = deg + p + 1; std::vector ret_coef(sdeg); for (unsigned int i = 0; i < p; i++) { ret_coef[i] = NT(0); } for (unsigned int i = p; i <= sdeg; i++) { ret_coef[i] = f[i-p]; } Polynomial ret(ret_coef.begin(), ret_coef.end()); return ret; #endif if ( p == 0 ) { return f; } int new_deg = f.degree() + p; if ( new_deg < 0 ) { return Polynomial(); } unsigned int unew_deg = new_deg; std::vector ret_coef(unew_deg+1); for (unsigned int i = 0; i < p; i++) { ret_coef[i] = NT(0); } for (unsigned int i = p; i <= unew_deg; i++) { ret_coef[i] = f[i-p]; } return Polynomial(ret_coef.begin(), ret_coef.end()); } protected: unsigned int p; }; } } } //namespace CGAL::POLYNOMIAL::internal #endif