1 /*
2     Copyright (C) 2021 Daniel Schultz
3 
4     This file is part of FLINT.
5 
6     FLINT is free software: you can redistribute it and/or modify it under
7     the terms of the GNU Lesser General Public License (LGPL) as published
8     by the Free Software Foundation; either version 2.1 of the License, or
9     (at your option) any later version.  See <https://www.gnu.org/licenses/>.
10 */
11 
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include "fmpz_mod_mpoly.h"
15 
16 int
main(void)17 main(void)
18 {
19     slong i, j, k;
20     FLINT_TEST_INIT(state);
21 
22     flint_printf("used_vars....");
23     fflush(stdout);
24 
25     for (i = 0; i < 20 * flint_test_multiplier(); i++)
26     {
27         fmpz_mod_mpoly_ctx_t ctx;
28         fmpz_mod_mpoly_t f;
29         fmpz_t one, fdeg;
30         slong len, var;
31         flint_bitcnt_t exp_bits;
32         int * used;
33 
34         fmpz_mod_mpoly_ctx_init_rand_bits(ctx, state, 20, 200);
35         fmpz_mod_mpoly_init(f, ctx);
36         fmpz_init(fdeg);
37         fmpz_init_set_ui(one, 1);
38         used = FLINT_ARRAY_ALLOC(ctx->minfo->nvars, int);
39 
40         for (j = 0; j < ctx->minfo->nvars; j++)
41         {
42             len = n_randint(state, 200);
43             exp_bits = n_randint(state, 150) + 2;
44 
45             fmpz_mod_mpoly_randtest_bits(f, state, len, exp_bits, ctx);
46 
47             for (k = n_randint(state, ctx->minfo->nvars); k > 0; k--)
48             {
49                 var = n_randint(state, ctx->minfo->nvars);
50                 fmpz_mod_mpoly_evaluate_one_fmpz(f, f, var, one, ctx);
51             }
52 
53             fmpz_mod_mpoly_used_vars(used, f, ctx);
54 
55             for (var = 0; var < ctx->minfo->nvars; var++)
56             {
57                 fmpz_mod_mpoly_degree_fmpz(fdeg, f, var, ctx);
58                 if ((fmpz_sgn(fdeg) <= 0) != !used[var])
59                 {
60                     flint_printf("FAIL: checked used matches degree\n");
61                     flint_printf("var = %wd\n", var);
62                     flint_printf("deg: "); fmpz_print(fdeg); flint_printf("\n");
63                     flint_abort();
64                 }
65             }
66         }
67 
68         flint_free(used);
69         fmpz_clear(one);
70         fmpz_clear(fdeg);
71         fmpz_mod_mpoly_clear(f, ctx);
72         fmpz_mod_mpoly_ctx_clear(ctx);
73     }
74 
75     FLINT_TEST_CLEANUP(state);
76 
77     flint_printf("PASS\n");
78     return 0;
79 }
80 
81