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_cot_pi(arb_t y,const arb_t x,slong prec)15 arb_cot_pi(arb_t y, const arb_t x, slong prec)
16 {
17
18 if (!arb_is_finite(x))
19 {
20 arb_indeterminate(y);
21 }
22 else if (arb_is_int_2exp_si(x, -1))
23 {
24 if (arb_is_int(x))
25 arb_indeterminate(y);
26 else
27 arb_zero(y);
28 }
29 else
30 {
31 arb_t u;
32 arb_init(u);
33 arb_sin_cos_pi(y, u, x, prec + 4);
34 arb_div(y, u, y, prec);
35 arb_clear(u);
36 }
37 }
38
39