1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
|
// Copyright (c) 1997
// Utrecht University (The Netherlands),
// ETH Zurich (Switzerland),
// INRIA Sophia-Antipolis (France),
// Max-Planck-Institute Saarbruecken (Germany),
// and Tel-Aviv University (Israel). 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: svn+ssh://scm.gforge.inria.fr/svn/cgal/branches/next/Algebraic_foundations/include/CGAL/number_utils_classes.h $
// $Id: number_utils_classes.h 67093 2012-01-13 11:22:39Z lrineau $
//
//
// Author(s) : Michael Hoffmann <hoffmann@inf.ethz.ch>
// : Michael Hemmer <hemmer@mpi-inf.mpg.de>
// to be included by number_utils.h
#ifndef CGAL_NUMBER_UTILS_CLASSES_H
#define CGAL_NUMBER_UTILS_CLASSES_H 1
#include <CGAL/number_type_basic.h>
#include <algorithm>
#include <utility>
namespace CGAL {
/* Defines functors:
- Is_zero
- Is_one
- Is_negative
- Is_positive
- Sgn
- Abs
- Compare
- Square
- Sqrt
- Div
- Gcd
- To_double
- To_interval
*/
template < class NT >
struct Is_negative : Real_embeddable_traits<NT>::Is_negative {};
template < class NT >
struct Is_positive : Real_embeddable_traits<NT>::Is_positive {};
template < class NT >
struct Abs : Real_embeddable_traits<NT>::Abs{};
template < class NT >
struct To_double : Real_embeddable_traits<NT>::To_double{};
template < class NT >
struct To_interval : Real_embeddable_traits<NT>::To_interval{};
// Sign would result in a name clash with enum.h
template < class NT >
struct Sgn : Real_embeddable_traits<NT>::Sgn {};
template < class NT >
struct Square : Algebraic_structure_traits<NT>::Square{};
template < class NT >
struct Sqrt : Algebraic_structure_traits<NT>::Sqrt {};
template < class NT >
struct Div : Algebraic_structure_traits<NT>::Div{};
template < class NT >
struct Gcd : Algebraic_structure_traits<NT>::Gcd{};
template < class NT >
struct Is_one : Algebraic_structure_traits<NT>::Is_one {};
// This is due to the fact that Is_zero may be provided by
// Algebraic_structure_traits as well as Real_embeddable_traits
// Of course it is not possible to derive from both since this
// would cause an ambiguity.
namespace internal{
template <class AST_Is_zero, class RET_Is_zero>
struct Is_zero_base : AST_Is_zero {} ;
template <class RET_Is_zero>
struct Is_zero_base <CGAL::Null_functor, RET_Is_zero >: RET_Is_zero {} ;
} // namespace internal
template < class NT >
struct Is_zero :
internal::Is_zero_base
<typename Algebraic_structure_traits<NT>::Is_zero,
typename Real_embeddable_traits<NT>::Is_zero>{};
// This is due to the fact that CGAL::Compare is used for other
// non-realembeddable types as well.
// In this case we try to provide a default implementation
namespace internal {
template <class NT, class Compare> struct Compare_base: public Compare {};
template <class NT> struct Compare_base<NT,Null_functor>
:public std::binary_function< NT, NT, Comparison_result > {
Comparison_result operator()( const NT& x, const NT& y) const
{
if (x < y) return SMALLER;
if (x > y) return LARGER;
CGAL_postcondition(x == y);
return EQUAL;
}
};
} // namespace internal
template < class NT >
struct Compare
:public internal::Compare_base
<NT,typename Real_embeddable_traits<NT>::Compare>{};
} //namespace CGAL
#endif // CGAL_NUMBER_UTILS_CLASSES_H
|
