* sysdeps/ieee754/ldbl-128/e_atanhl.c: New file, contributed by
	Stephen L Moshier.
This commit is contained in:
Andreas Jaeger 2001-07-30 09:08:38 +00:00
parent 47da6f7128
commit dd98116c60
3 changed files with 88 additions and 1 deletions

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@ -1,5 +1,8 @@
2001-07-30 Andreas Jaeger <aj@suse.de>
* sysdeps/ieee754/ldbl-128/e_atanhl.c: New file, contributed by
Stephen L Moshier.
* posix/regex.c: Declare wcs functions only if compiling with
MBS_SUPPORT.
Don't use #elif for traditional C.

2
NEWS
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@ -9,7 +9,7 @@ Please send GNU C library bug reports using the `glibcbug' script to
Version 2.2.4
* Stephen Moshier implemented cosh, expm1, log1p, acos, sinh, tanh,
asinh for the 128-bit long double format.
asinh, atanh for the 128-bit long double format.
* Bruno Haible updated all the code handling Unicode in some form to
support Unicode 3.1.

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@ -0,0 +1,84 @@
/* s_atanhl.c -- long double version of s_atan.c.
* Conversion to long double by Ulrich Drepper,
* Cygnus Support, drepper@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: $";
#endif
/* __ieee754_atanhl(x)
* Method :
* 1.Reduced x to positive by atanh(-x) = -atanh(x)
* 2.For x>=0.5
* 1 2x x
* atanhl(x) = --- * log(1 + -------) = 0.5 * log1p(2 * --------)
* 2 1 - x 1 - x
*
* For x<0.5
* atanhl(x) = 0.5*log1pl(2x+2x*x/(1-x))
*
* Special cases:
* atanhl(x) is NaN if |x| > 1 with signal;
* atanhl(NaN) is that NaN with no signal;
* atanhl(+-1) is +-INF with signal.
*
*/
#include "math.h"
#include "math_private.h"
#ifdef __STDC__
static const long double one = 1.0L, huge = 1e4900L;
#else
static long double one = 1.0L, huge = 1e4900L;
#endif
#ifdef __STDC__
static const long double zero = 0.0L;
#else
static double long zero = 0.0L;
#endif
#ifdef __STDC__
long double __ieee754_atanhl(long double x)
#else
long double __ieee754_atanhl(x)
long double x;
#endif
{
long double t;
u_int32_t jx, ix;
ieee854_long_double_shape_type u;
u.value = x;
jx = u.parts32.w0;
ix = jx & 0x7fffffff;
u.parts32.w0 = ix;
if (ix >= 0x3fff0000) /* |x| >= 1.0 or infinity or NaN */
{
if (u.value == one)
return x/zero;
else
return (x-x)/(x-x);
}
if(ix<0x3fc60000 && (huge+x)>zero) return x; /* x < 2^-57 */
if(ix<0x3ffe0000) { /* x < 0.5 */
t = u.value+u.value;
t = 0.5*__log1pl(t+t*u.value/(one-u.value));
} else
t = 0.5*__log1pl((u.value+u.value)/(one-u.value));
if(jx & 0x80000000) return -t; else return t;
}