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
|
#ifndef __montableZZ_h
#define __montableZZ_h
#include "buffer.hpp"
#include "newdelete.hpp"
#include "style.hpp"
#include <vector>
#include <memory>
#include <algorithm>
#include <stdio.h>
#include <stddef.h>
/* "Tricks" used in this implementation */
/*
1. exponent vectors: these look like: [e1, ..., en],
where n is the number of variables. HOWEVER, these
exponents are never created or freed by these routines,
so if they have more entries (e.g. a "sugar" homogenization)
then that (those) value(s) are ignored.
2. comparison routine: elements are kept in (increasing?) lex order.
Is this really an OK idea?
*/
typedef int *exponents;
class MonomialTableZZ : public our_new_delete
{
public:
struct mon_term : public our_new_delete
{
mon_term *_next;
mon_term *_prev;
exponents _lead; /* Who owns this? */
unsigned long _mask;
int _val;
mpz_srcptr _coeff; /* If not given, this is NULL. Ig given, it points to data elsewhere (e.g. a GB) which will outlive this data */
};
static MonomialTableZZ *make(int nvars);
/* Create a zero element table */
~MonomialTableZZ();
void insert(mpz_srcptr coeff, exponents exp, int comp, int id);
/* Insert [coeff,exp,comp,id] into the table. If there is already
an element which is <= [exp,comp], this triple is still
inserted. If that is not desired, use find_divisors.
*/
bool is_weak_member(mpz_srcptr c, exponents exp, int comp) const;
// Is [c,exp,comp] in the submodule generated by the terms in 'this'?
// Maybe a gbvector should be returned?
bool is_strong_member(mpz_srcptr c, exponents exp, int comp) const;
// Is [c,exp,comp] divisible by one of the terms in 'this'?
int find_smallest_coeff_divisor(exponents exp, int comp) const;
// Of all of the elements which divide exp*comp, return the index of the
// smallest coefficient one, or return -1, if no element divides exp*comp.
int find_term_divisors(int max,
mpz_srcptr coeff,
exponents exp,
int comp,
VECTOR(mon_term *) *result = 0) const;
/* max: the max number of divisors to find.
exp: the monomial whose divisors we seek.
result: an array of mon_term's.
return value: length of this array, i.e. the number of matches found */
int find_monomial_divisors(int max,
exponents exp,
int comp,
VECTOR(mon_term *) *result = 0) const;
mon_term *find_exact(mpz_srcptr coeff, exponents exp, int comp) const;
/* If this returns non-NULL, it is valid to grab the 'val' field, and/or to
assign to it.
All other fields should be considered read only */
mon_term *find_exact_monomial(exponents exp, int comp, int first_val) const;
// Is there an element 'exp*comp' with _val >= first_val? If so, return the
// mon_term.
// Otherwise return 0.
void change_coefficient(mon_term *t, mpz_srcptr new_coeff, int new_id);
static void find_weak_generators(int nvars,
const VECTOR(mpz_srcptr) & coeffs,
const VECTOR(exponents) & exps,
const VECTOR(int) & comps,
VECTOR(int) & result_positions,
bool use_stable_sort = true);
static void find_strong_generators(int nvars,
const VECTOR(mpz_srcptr) & coeffs,
const VECTOR(exponents) & exps,
const VECTOR(int) & comps,
VECTOR(int) & result_positions);
void show_mon_term(FILE *fil, mon_term *t) const; /* Only for debugging */
void show_mon_term(buffer &o, mon_term *t) const; /* Only for debugging */
void show_mon_term(buffer &o,
mpz_srcptr coeff,
exponents lead,
int comp) const; /* Only for debugging */
void show(FILE *fil) const; /* Only for debugging */
void showmontable();
void show_weak(FILE *fil,
mpz_srcptr coeff,
exponents exp,
int comp,
int val) const; /* Debugging */
private:
int _nvars;
int _count;
VECTOR(mon_term *) _head; /* One per component */
static mon_term *make_list_head();
};
#endif
// Local Variables:
// compile-command: "make -C $M2BUILDDIR/Macaulay2/e "
// indent-tabs-mode: nil
// End:
|
