// 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_DERIVATIVE_H #define CGAL_POLYNOMIAL_INTERNAL_DERIVATIVE_H #include #include #include namespace CGAL { namespace POLYNOMIAL { namespace internal { template struct Derivative { private: typedef typename Fn::iterator Cit; struct It : public boost::iterator_facade::value_type, typename std::iterator_traits::iterator_category, // Use value_type as reference (see // dereference() below()) typename std::iterator_traits::value_type, typename std::iterator_traits::difference_type> { It(Cit it, int i): i_(i), cit_(it) {} It(){} private: typedef typename Fn::iterator MCit; typedef typename std::iterator_traits Traits; public: typedef typename Traits::difference_type difference_type; typedef typename Traits::value_type value_type; private: friend class boost::iterator_core_access; value_type dereference() const { return value_type(i_)**cit_; } void increment() { ++i_; ++cit_;} bool equal(const It& i) const { return (i_ == i.i_) && (cit_ == i.cit_); } void decrement() { --i_; --cit_;} void advance(const difference_type n) { i_ += n; cit_ += n; } difference_type distance_to(const It& o) const { return o.cit_ - cit_; } protected: int i_; MCit cit_; }; // end nested struct It public: typedef Fn result_type; typedef Fn argument_type; result_type operator()(const argument_type &o) const { if (o.is_constant()) { return result_type(typename result_type::NT(0)); } else { It b(o.begin(),0); ++b; return result_type(b, It(o.end(), o.degree()+1)); } } void write(std::ostream &out) const { out << "diff"; } }; } } } //namespace CGAL::POLYNOMIAL::internal #endif