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
/*
Copyright (C) 2023 Jean Kieffer
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 "acb.h"
#include "acb_mat.h"
#include "acb_theta.h"
void
acb_siegel_randtest_vec_reduced(acb_ptr zs, flint_rand_t state, slong nb,
const acb_mat_t tau, int exact, slong prec)
{
slong g = acb_mat_nrows(tau);
arb_t t;
slong j;
/* Sample z in [-1,1] + tau[-1,1] */
arb_init(t);
_acb_vec_zero(zs, nb * g);
for (j = 0; j < nb * g; j++)
{
arb_urandom(acb_realref(&zs[j]), state, prec);
acb_mul_2exp_si(&zs[j], &zs[j], 1);
acb_sub_si(&zs[j], &zs[j], 1, prec);
}
for (j = 0; j < nb; j++)
{
acb_mat_vector_mul_col(zs + j * g, tau, zs + j * g, prec);
}
for (j = 0; j < nb * g; j++)
{
arb_urandom(t, state, prec);
arb_mul_2exp_si(t, t, 1);
arb_sub_si(t, t, 1, prec);
acb_add_arb(&zs[j], &zs[j], t, prec);
}
if (exact)
{
for (j = 0; j < nb * g; j++)
{
acb_get_mid(&zs[j], &zs[j]);
}
}
/* Sometimes, force zeros */
for (j = 0; j < nb; j++)
{
if (n_randint(state, 5) == 0)
{
_acb_vec_zero(zs + j * g, g);
}
}
arb_clear(t);
}