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  • Committer: Package Import Robot
  • Author(s): Matthias Klose
  • Date: 2012-02-08 01:58:09 UTC
  • mfrom: (1.5.3) (288.1.12 precise)
  • Revision ID: package-import@ubuntu.com-20120208015809-ulscst7uteq3e22z
Tags: 2.15~pre6-0ubuntu10
Merge from Debian (r5151, 2.13-26).

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sysdeps/ieee754/ldbl-96/e_atanhl.c
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 * ====================================================
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 */
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#if defined(LIBM_SCCS) && !defined(lint)
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static char rcsid[] = "$NetBSD: $";
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#endif
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/* __ieee754_atanhl(x)
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 * Method :
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 *    1.Reduced x to positive by atanh(-x) = -atanh(x)
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 *      atanhl(x) = --- * log(1 + -------) = 0.5 * log1p(2 * --------)
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 *                   2             1 - x                      1 - x
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 *
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 *      For x<0.5
 
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 *      For x<0.5
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 *      atanhl(x) = 0.5*log1pl(2x+2x*x/(1-x))
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 *
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 * Special cases:
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#include "math.h"
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#include "math_private.h"
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#ifdef __STDC__
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static const long double one = 1.0, huge = 1e4900L;
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#else
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static long double one = 1.0, huge = 1e4900L;
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#endif
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#ifdef __STDC__
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static const long double zero = 0.0;
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#else
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static double long zero = 0.0;
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#endif
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#ifdef __STDC__
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        long double __ieee754_atanhl(long double x)
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#else
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        long double __ieee754_atanhl(x)
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        long double x;
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#endif
 
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long double
 
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__ieee754_atanhl(long double x)
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{
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        long double t;
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        int32_t ix;
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            return (x-x)/(x-x);
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        if(ix==0x3fff)
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            return x/zero;
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        if(ix<0x3fe3&&(huge+x)>zero) return x;  /* x<2**-28 */
 
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        if(ix<0x3fe3) {
 
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            math_force_eval(huge+x);
 
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            return x;   /* x<2**-28 */
 
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        }
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        SET_LDOUBLE_EXP(x,ix);
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        if(ix<0x3ffe) {         /* x < 0.5 */
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            t = x+x;
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            t = 0.5*__log1pl((x+x)/(one-x));
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        if(se<=0x7fff) return t; else return -t;
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}
 
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strong_alias (__ieee754_atanhl, __atanhl_finite)