diff options
Diffstat (limited to 'math/s_catanh.c')
| -rw-r--r-- | math/s_catanh.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/math/s_catanh.c b/math/s_catanh.c index 55c56283b3..5248cbc0c8 100644 --- a/math/s_catanh.c +++ b/math/s_catanh.c @@ -89,7 +89,25 @@ __catanh (__complex__ double x) __real__ res = 0.25 * __log1p (num / den); } - den = 1 - __real__ x * __real__ x - i2; + double absx, absy; + + absx = fabs (__real__ x); + absy = fabs (__imag__ x); + if (absx < absy) + { + double t = absx; + absx = absy; + absy = t; + } + + if (absx >= 1.0) + den = (1.0 - absx) * (1.0 + absx) - absy * absy; + else if (absx >= 0.75 && absy < DBL_EPSILON / 2.0) + den = (1.0 - absx) * (1.0 + absx); + else if (absx >= 0.75 || absy >= 0.5) + den = -__x2y2m1 (absx, absy); + else + den = (1.0 - absx) * (1.0 + absx) - absy * absy; __imag__ res = 0.5 * __ieee754_atan2 (2.0 * __imag__ x, den); } |