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 #include "acb.h"
14
15 void
arb_hurwitz_zeta(arb_t res,const arb_t s,const arb_t z,slong prec)16 arb_hurwitz_zeta(arb_t res, const arb_t s, const arb_t z, slong prec)
17 {
18 if (!arb_contains_si(s, 1) &&
19 (arb_is_positive(z) ||
20 (arb_is_int(z) && arb_is_int(s) && arb_is_nonpositive(s))))
21 {
22 acb_t a, b, c;
23
24 acb_init(a);
25 acb_init(b);
26 acb_init(c);
27
28 acb_set_arb(a, s);
29 acb_set_arb(b, z);
30 acb_hurwitz_zeta(c, a, b, prec);
31 arb_set(res, acb_realref(c));
32
33 acb_clear(a);
34 acb_clear(b);
35 acb_clear(c);
36 }
37 else
38 {
39 arb_indeterminate(res);
40 }
41 }
42
43