1 /*
2 Copyright (C) 2013 Fredrik Johansson
3
4 This file is part of Arb.
5
6 Arb 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 <http://www.gnu.org/licenses/>.
10 */
11
12 #include "arb.h"
13
14 void
arb_tan_pi(arb_t y,const arb_t x,slong prec)15 arb_tan_pi(arb_t y, const arb_t x, slong prec)
16 {
17 if (!arb_is_finite(x))
18 {
19 arb_indeterminate(y);
20 }
21 else if (arb_is_int_2exp_si(x, -1))
22 {
23 if (arb_is_int(x))
24 arb_zero(y);
25 else
26 arb_indeterminate(y);
27 }
28 else
29 {
30 arb_t u;
31 arb_init(u);
32 arb_sin_cos_pi(y, u, x, prec + 4);
33 arb_div(y, y, u, prec);
34 arb_clear(u);
35 }
36 }
37
38