newlib-cygwin/winsup/cygwin/math/ctan.def.h

/*
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*/

__FLT_TYPE __complex__ __cdecl
__FLT_ABI(ctan) (__FLT_TYPE __complex__ z)
{
  /* Annex G.6: ctan(z) = -i ctanh (iz) */
  __complex__ __FLT_TYPE ret;
  __complex__ __FLT_TYPE x;

  __real__ x = -__imag__ z;
  __imag__ x = __real__ z;

  x = __FLT_ABI(ctanh) (x);

  __real__ ret = __imag__ x;
  __imag__ ret = -__real__ x;

  return ret;
}