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
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

/*
    Copyright (C) 2020 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 "test_helpers.h"
#include "fmpz_mpoly_factor.h"

void check_content(const fmpz_mpoly_t p, const fmpz_mpoly_ctx_t ctx)
{
    slong i, v;
    fmpz_mpoly_t q;
    fmpz_mpoly_factor_t g;
    fmpz_t deg;

    fmpz_mpoly_factor_init(g, ctx);
    fmpz_mpoly_init(q, ctx);
    fmpz_init(deg);

    if (!fmpz_mpoly_factor_content(g, p, ctx))
    {
        flint_printf("FAIL:\ncheck factorization could be computed\n");
        fflush(stdout);
        flint_abort();
    }

    for (i = 0; i < g->num; i++)
    {
        if (g->poly[i].length < 1 || fmpz_sgn(g->poly[i].coeffs + 0) < 0)
        {
            flint_printf("FAIL:\nfactorization is not unit normal\n");
            fflush(stdout);
            flint_abort();
        }
    }

    fmpz_mpoly_factor_expand(q, g, ctx);
    if (!fmpz_mpoly_equal(q, p, ctx))
    {
        flint_printf("FAIL:\nfactorization does not match original polynomial\n");
        fflush(stdout);
        flint_abort();
    }

    for (i = 0; i < g->num; i++)
    {
        for (v = 0; v < ctx->minfo->nvars; v++)
        {
            if (fmpz_mpoly_length(g->poly + i, ctx) < 2)
            {
                if (!fmpz_mpoly_is_gen(g->poly + i, -1, ctx))
                {
                    flint_printf("FAIL:\nmonomial is bad\n");
                    fflush(stdout);
                    flint_abort();
                }
            }
            else
            {
                if (!fmpz_mpoly_content_vars(q, g->poly + i, &v, 1, ctx))
                {
                    flint_printf("FAIL:\ncheck content could be computed\n");
                    fflush(stdout);
                    flint_abort();
                }

                fmpz_mpoly_degree_fmpz(deg, g->poly + i, v, ctx);
                if (!fmpz_mpoly_is_one(q, ctx) && !fmpz_is_zero(deg))
                {
                    flint_printf("FAIL:\ncontent is bad\n");
                    fflush(stdout);
                    flint_abort();
                }
            }
        }
    }

    fmpz_mpoly_clear(q, ctx);
    fmpz_mpoly_factor_clear(g, ctx);
    fmpz_clear(deg);
}

TEST_FUNCTION_START(fmpz_mpoly_factor_content, state)
{
    slong i, j, k, tmul = 30;

    for (i = 0; i < tmul * flint_test_multiplier(); i++)
    {
        fmpz_mpoly_ctx_t ctx;
        fmpz_mpoly_t a, t;
        slong n, nfacs, len;
        ulong * expbounds;
        flint_bitcnt_t coeffbits;

        fmpz_mpoly_ctx_init_rand(ctx, state, 10);

        fmpz_mpoly_init(a, ctx);
        fmpz_mpoly_init(t, ctx);

        n = FLINT_MAX(WORD(1), ctx->minfo->nvars);
        nfacs = 5 + (8 + n_randint(state, 8))/n;
        expbounds = FLINT_ARRAY_ALLOC(ctx->minfo->nvars, ulong);
        for (k = 0; k < ctx->minfo->nvars; k++)
            expbounds[k] = 3;

        fmpz_mpoly_one(a, ctx);
        for (j = 0; j < nfacs; j++)
        {
            len = 1 + n_randint(state, 9);
            coeffbits = 2 + n_randint(state, 100);
            if (ctx->minfo->nvars > 0)
            {
                k = n_randint(state, ctx->minfo->nvars);
                expbounds[k] = 1;
            }
            fmpz_mpoly_randtest_bounds(t, state, len, coeffbits, expbounds, ctx);

            if (!fmpz_mpoly_is_zero(t, ctx))
            {
                fmpz_mpoly_mul(t, a, t, ctx);
                if (t->length < 1500)
                    fmpz_mpoly_swap(a, t, ctx);
            }
        }

        check_content(a, ctx);

        flint_free(expbounds);
        fmpz_mpoly_clear(t, ctx);
        fmpz_mpoly_clear(a, ctx);
        fmpz_mpoly_ctx_clear(ctx);
    }

    TEST_FUNCTION_END(state);
}