flint-sys 0.9.0

Bindings to the FLINT C library
Documentation 
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

/*
    Copyright (C) 2017, 2018 Daniel Schultz

    This file is part of FLINT.

    FLINT is free software: you can redistribute it and/or modify it under
    the terms of the GNU Lesser General Public License (LGPL) as published
    by the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.  See <https://www.gnu.org/licenses/>.
*/

#include "nmod.h"
#include "mpoly.h"
#include "nmod_mpoly.h"

static int _nmod_mpoly_equal(const ulong * coeff1, const ulong * exp1,
                      const ulong * coeff2, const ulong * exp2,
                                                            slong len, slong N)
{
    slong i;

    if (coeff1 != coeff2)
    {
        for (i = 0; i < len; i++)
            if (coeff1[i] != coeff2[i])
                return 0;
    }

    if (exp1 != exp2)
    {
        for (i = 0; i < len; i++)
            if (!mpoly_monomial_equal(exp1 + N*i, exp2 + N*i, N))
                return 0;
    }

    return 1;
}

int nmod_mpoly_equal(const nmod_mpoly_t poly1, const nmod_mpoly_t poly2,
                                                    const nmod_mpoly_ctx_t ctx)
{
    ulong * ptr1 = poly1->exps, * ptr2 = poly2->exps;
    ulong max_bits;
    slong N;
    int r, free1 = 0, free2 = 0;

    if (poly1 == poly2)
        return 1;

    if (poly1->length != poly2->length)
        return 0;

    max_bits = FLINT_MAX(poly1->bits, poly2->bits);
    N = mpoly_words_per_exp(max_bits, ctx->minfo);

    if (max_bits > poly1->bits)
    {
        free1 = 1;
        ptr1 = (ulong *) flint_malloc(N*poly1->length*sizeof(ulong));
        mpoly_repack_monomials(ptr1, max_bits, poly1->exps, poly1->bits,
                                                    poly1->length, ctx->minfo);
    }

    if (max_bits > poly2->bits)
    {
        free2 = 1;
        ptr2 = (ulong *) flint_malloc(N*poly2->length*sizeof(ulong));
        mpoly_repack_monomials(ptr2, max_bits, poly2->exps, poly2->bits,
                                                    poly2->length, ctx->minfo);
    }

    r = _nmod_mpoly_equal(poly1->coeffs, ptr1,
                                        poly2->coeffs, ptr2, poly2->length, N);

    if (free1)
        flint_free(ptr1);

    if (free2)
        flint_free(ptr2);

    return r;
}

int nmod_mpoly_equal_ui(const nmod_mpoly_t A,
                                           ulong c, const nmod_mpoly_ctx_t ctx)
{
    slong N;

    if (c >= ctx->mod.n)
        NMOD_RED(c, c, ctx->mod);

    if (c == 0)
        return A->length == 0;

    if (A->length != 1)
        return 0;

    N = mpoly_words_per_exp(A->bits, ctx->minfo);

    if (!mpoly_monomial_is_zero(A->exps + N*0, N))
        return 0;

    return A->coeffs[0] == c;
}