diff options
Diffstat (limited to 'sysdeps/generic/s_ctan.c')
| -rw-r--r-- | sysdeps/generic/s_ctan.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/sysdeps/generic/s_ctan.c b/sysdeps/generic/s_ctan.c index 6a09fe465b..0464ab86d5 100644 --- a/sysdeps/generic/s_ctan.c +++ b/sysdeps/generic/s_ctan.c @@ -1,5 +1,5 @@ /* Complex tangent function for double. - Copyright (C) 1997 Free Software Foundation, Inc. + Copyright (C) 1997, 2005 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. @@ -61,8 +61,18 @@ __ctan (__complex__ double x) den = cos2rx + __ieee754_cosh (2.0 * __imag__ x); - __real__ res = sin2rx / den; - __imag__ res = __ieee754_sinh (2.0 * __imag__ x) / den; + if (den == 0.0) + { + __complex__ double ez = __cexp (1.0i * x); + __complex__ double emz = __cexp (-1.0i * x); + + res = (ez - emz) / (ez + emz) * -1.0i; + } + else + { + __real__ res = sin2rx / den; + __imag__ res = __ieee754_sinh (2.0 * __imag__ x) / den; + } } return res; |