diff options
| author | Joseph Myers <joseph@codesourcery.com> | 2013-03-21 10:27:10 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2013-03-21 10:27:10 +0000 |
| commit | 0a1b2ae6f6d511519ab3c0ccbf54982ae65bc444 (patch) | |
| tree | ffa27d00584d224e4b47a9654e192fb3fb0ed0ba /math/k_casinhl.c | |
| parent | b33d4ce4a2a05ca8a29798f410657e43722193ff (diff) | |
Fix casinh inaccuracy for argument with imaginary part 1 (bug 15287).
Diffstat (limited to 'math/k_casinhl.c')
| -rw-r--r-- | math/k_casinhl.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/math/k_casinhl.c b/math/k_casinhl.c index aec501b079..eb090ec3ce 100644 --- a/math/k_casinhl.c +++ b/math/k_casinhl.c @@ -84,6 +84,32 @@ __kernel_casinhl (__complex__ long double x, int adj) else __imag__ res = __ieee754_atan2l (s, rx); } + else if (ix == 1.0L && rx < 0.5L) + { + if (rx < LDBL_EPSILON / 8.0L) + { + __real__ res = __log1pl (2.0L * (rx + __ieee754_sqrtl (rx))) / 2.0L; + if (adj) + __imag__ res = __ieee754_atan2l (__ieee754_sqrtl (rx), + __copysignl (1.0L, __imag__ x)); + else + __imag__ res = __ieee754_atan2l (1.0L, __ieee754_sqrtl (rx)); + } + else + { + long double d = rx * __ieee754_sqrtl (4.0L + rx * rx); + long double s1 = __ieee754_sqrtl ((d + rx * rx) / 2.0L); + long double s2 = __ieee754_sqrtl ((d - rx * rx) / 2.0L); + + __real__ res = __log1pl (rx * rx + d + 2.0L * (rx * s1 + s2)) / 2.0L; + if (adj) + __imag__ res = __ieee754_atan2l (rx + s1, + __copysignl (1.0L + s2, + __imag__ x)); + else + __imag__ res = __ieee754_atan2l (1.0L + s2, rx + s1); + } + } else { __real__ y = (rx - ix) * (rx + ix) + 1.0L; |