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
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
/* Copyright (c) 1997-2024
Ewgenij Gawrilow, Michael Joswig, and the polymake team
Technische Universität Berlin, Germany
https://polymake.org
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version: http://www.gnu.org/licenses/gpl.txt.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
--------------------------------------------------------------------------------
*/
#pragma once
#include "polymake/Integer.h"
#include "polymake/internal/converters_basic_defs.h"
#include <iostream>
#include <polymake/GenericIO.h>
#include <limits>
namespace pm {
class GF2 {
protected:
bool boolrep;
public:
GF2() : boolrep(false) {}
explicit GF2(const Int& n) : boolrep(n % 2) {}
explicit GF2(const Integer& n) : boolrep(n % 2) {}
GF2(const GF2& gf2) : boolrep(gf2.to_bool()) {}
inline bool to_bool() const {
return boolrep;
}
// arithmetic operations:
GF2& negate()
{
return *this;
}
friend GF2 operator+ (const GF2& a, const GF2& b) { return GF2(a.to_bool() != b.to_bool()); }
friend GF2 operator- (const GF2& a, const GF2& b) { return a+b; }
friend GF2 operator* (const GF2& a, const GF2& b) { return GF2(a.to_bool() && b.to_bool()); }
friend GF2 operator/ (const GF2& a, const GF2& b) {
if (!b.to_bool())
throw std::domain_error("Divide by zero exception");
return a;
}
inline GF2& operator+= (const GF2& a) { return (*this = *this + a); }
inline GF2& operator-= (const GF2& a) { return (*this += a); }
inline GF2& operator*= (const GF2& a) { return (*this = *this * a); }
inline GF2& operator/= (const GF2& a) { return (*this = *this / a); }
inline GF2& operator++ () { return (*this += GF2(1)); }
inline GF2& operator-- () { return (*this -= GF2(1)); }
friend GF2 operator- (const GF2& a) { return a; }
friend bool operator== (const GF2& a, const GF2& b) { return a.boolrep == b.boolrep; }
friend bool operator!= (const GF2& a, const GF2& b) { return !(a == b); }
// I/O:
protected:
// TODO why is this here?
template <typename Input>
Input& read(Input& in)
{
return in >> boolrep;
}
public:
template <typename Input> friend
Input& operator>> (GenericInput<Input>& in, GF2& me)
{
return in.top() >> me.boolrep;
}
template <typename Output> friend
Output& operator<< (GenericOutput<Output>& out, const GF2& me)
{
return out.top() << me.to_bool();
}
};
template <typename T, bool _is_integer=std::numeric_limits<T>::is_integer>
class conv_to_GF2;
template <typename T>
class conv_to_GF2<T, true> {
public:
typedef T argument_type;
typedef GF2 result_type;
result_type operator() (typename pm::function_argument<T>::type x) const { return result_type(x%2); }
};
template <>
struct choose_generic_object_traits<pm::GF2, false, false> :
spec_object_traits< is_scalar > {
typedef void generic_type;
typedef is_scalar generic_tag;
typedef pm::GF2 persistent_type;
static bool is_zero(const pm::GF2& a) {
return !a.to_bool();
}
static bool is_one(const pm::GF2& a) {
return a.to_bool();
}
static const persistent_type& zero() {
static pm::GF2 zero = pm::GF2(0);
return zero;
}
static const persistent_type& one() {
static pm::GF2 one = pm::GF2(1);
return one;
}
};
template <>
struct algebraic_traits<pm::GF2> {
typedef pm::GF2 field_type;
};
template <>
struct hash_func<GF2, is_scalar> {
size_t operator() (const GF2& a) const
{
return a.to_bool();
}
};
}
namespace polymake {
using pm::GF2;
}
// Local Variables:
// mode:C++
// c-basic-offset:3
// indent-tabs-mode:nil
// End:
|
