cgal/Kinetic_data_structures/include/CGAL/Polynomial/internal/Rational/Derivative.h

123 lines
2.8 KiB
C++

// 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; version 2.1 of the License.
// See the file LICENSE.LGPL distributed with CGAL.
//
// 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 <drussel@alumni.princeton.edu>
#ifndef CGAL_POLYNOMIAL_INTERNAL_DERIVATIVE_H
#define CGAL_POLYNOMIAL_INTERNAL_DERIVATIVE_H
#include <CGAL/Polynomial/basic.h>
#include <iterator>
CGAL_POLYNOMIAL_BEGIN_INTERNAL_NAMESPACE
template <class Fn>
struct Derivative
{
private:
typedef typename Fn::iterator Cit;
struct It
{
It(Cit it, int i): i_(i), cit_(it) {}
It(){}
typedef typename Fn::iterator MCit;
typedef typename std::iterator_traits<MCit> Traits;
typedef typename Traits::iterator_category iterator_category;
typedef typename Traits::value_type value_type;
typedef typename Traits::pointer pointer;
typedef typename Traits::reference reference;
typedef typename Traits::difference_type difference_type;
value_type operator*() const
{
return value_type(i_)**cit_;
}
pointer operator->() const
{
return value_type(i_)**cit_;
}
bool operator<(It o) const
{
return cit_ < o.cit_;
}
It operator++() {
++i_;
++cit_;
return *this;
}
It operator++(int) {
It t=*this;
++i_;
++cit_;
return t;
}
It operator--() {
--i_;
--cit_;
return *this;
}
It operator--(int) {
It t=*this;
--i_;
--cit_;
return t;
}
bool operator==(It o) const
{
return cit_ == o.cit_;
}
bool operator!=(It o) const
{
return cit_ != o.cit_;
}
difference_type operator-(It o) const
{
return cit_-o.cit_;
}
It operator+=(difference_type i) {
cit_+= i;
i_+= i;
return *this;
}
protected:
int i_;
MCit cit_;
};
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";
}
};
CGAL_POLYNOMIAL_END_INTERNAL_NAMESPACE
#endif