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 /*							zetac.c
 *
 *	Riemann zeta function
 *
 *
 *
 * SYNOPSIS:
 *
 * double x, y, zetac();
 *
 * y = zetac( x );
 *
 *
 *
 * DESCRIPTION:
 *
 *
 *
 *                inf.
 *                 -    -x
 *   zetac(x)  =   >   k   ,   x > 1,
 *                 -
 *                k=2
 *
 * is related to the Riemann zeta function by
 *
 *	Riemann zeta(x) = zetac(x) + 1.
 *
 * Extension of the function definition for x < 1 is implemented.
 * Zero is returned for x > md_log2(MAXNUM).
 *
 * An overflow error may occur for large negative x, due to the
 * md_gamma function in the reflection formula.
 *
 * ACCURACY:
 *
 * Tabulated values have full machine accuracy.
 *
 *                      Relative error:
 * arithmetic   domain     # trials      peak         rms
 *    IEEE      1,50        10000       9.8e-16	    1.3e-16
 *    DEC       1,50         2000       1.1e-16     1.9e-17
 *
 *
 */

/*
Cephes Math Library Release 2.8:  June, 2000
Copyright 1984, 1987, 1989, 2000 by Stephen L. Moshier
*/

#include "mconf.h"

extern double MAXNUM, PI;

/* Riemann zeta(x) - 1
 * for integer arguments between 0 and 30.
 */
#ifdef UNK
static double azetac[] = {
-1.50000000000000000000E0,
 1.70141183460469231730E38, /* infinity. */
 6.44934066848226436472E-1,
 2.02056903159594285400E-1,
 8.23232337111381915160E-2,
 3.69277551433699263314E-2,
 1.73430619844491397145E-2,
 8.34927738192282683980E-3,
 4.07735619794433937869E-3,
 2.00839282608221441785E-3,
 9.94575127818085337146E-4,
 4.94188604119464558702E-4,
 2.46086553308048298638E-4,
 1.22713347578489146752E-4,
 6.12481350587048292585E-5,
 3.05882363070204935517E-5,
 1.52822594086518717326E-5,
 7.63719763789976227360E-6,
 3.81729326499983985646E-6,
 1.90821271655393892566E-6,
 9.53962033872796113152E-7,
 4.76932986787806463117E-7,
 2.38450502727732990004E-7,
 1.19219925965311073068E-7,
 5.96081890512594796124E-8,
 2.98035035146522801861E-8,
 1.49015548283650412347E-8,
 7.45071178983542949198E-9,
 3.72533402478845705482E-9,
 1.86265972351304900640E-9,
 9.31327432419668182872E-10
};
#endif