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/*						rgamma.c
 *
 *	Reciprocal md_gamma function
 *
 *
 *
 * SYNOPSIS:
 *
 * double x, y, rgamma();
 *
 * y = rgamma( x );
 *
 *
 *
 * DESCRIPTION:
 *
 * Returns one divided by the md_gamma function of the argument.
 *
 * The function is approximated by a Chebyshev expansion in
 * the interval [0,1].  Range reduction is by recurrence
 * for arguments between -34.034 and +34.84425627277176174.
 * 1/MAXNUM is returned for positive arguments outside this
 * range.  For arguments less than -34.034 the cosecant
 * reflection formula is applied; lograrithms are employed
 * to avoid unnecessary overflow.
 *
 * The reciprocal md_gamma function has no singularities,
 * but overflow and underflow may occur for large arguments.
 * These conditions return either MAXNUM or 1/MAXNUM with
 * appropriate sign.
 *
 * ACCURACY:
 *
 *                      Relative error:
 * arithmetic   domain     # trials      peak         rms
 *    DEC      -30,+30       4000       1.2e-16     1.8e-17
 *    IEEE     -30,+30      30000       1.1e-15     2.0e-16
 * For arguments less than -34.034 the peak error is on the
 * order of 5e-15 (DEC), excepting overflow or underflow.
 */

/*
Cephes Math Library Release 2.8:  June, 2000
Copyright 1985, 1987, 2000 by Stephen L. Moshier
*/

#include "mconf.h"

/* Chebyshev coefficients for reciprocal md_gamma function
 * in interval 0 to 1.  Function is 1/(x md_gamma(x)) - 1
 */

#ifdef UNK
static double R[] = {
 3.13173458231230000000E-17,
-6.70718606477908000000E-16,
 2.20039078172259550000E-15,
 2.47691630348254132600E-13,
-6.60074100411295197440E-12,
 5.13850186324226978840E-11,
 1.08965386454418662084E-9,
-3.33964630686836942556E-8,
 2.68975996440595483619E-7,
 2.96001177518801696639E-6,
-8.04814124978471142852E-5,
 4.16609138709688864714E-4,
 5.06579864028608725080E-3,
-6.41925436109158228810E-2,
-4.98558728684003594785E-3,
 1.27546015610523951063E-1
};
#endif

#ifdef DEC
static unsigned short R[] = {
0022420,0066376,0176751,0071636,
0123501,0051114,0042104,0131153,
0024036,0107013,0126504,0033361,
0025613,0070040,0035174,0162316,
0126750,0037060,0077775,0122202,
0027541,0177143,0037675,0105150,
0030625,0141311,0075005,0115436,
0132017,0067714,0125033,0014721,
0032620,0063707,0105256,0152643,