Use of C99 extra long double math functions after r236148

[Stephen Montgomery-Smith]

On 07/22/2012 11:56 PM, Stephen Montgomery-Smith wrote:
> This is the work I have done to produce casinh, casin, cacos and cacosh.
>   The latter two took me a lot more time than I expected.  It took me a
> lot of time to try to find the correct branches.
>
>


Once I have cacos, cacosh turns out to be much easier than I thought:

double complex
cacosh(double complex z)
{
	complex double w;

	w = cacos(z);
	if (signbit(cimag(w)) == 0)
		return cpack(cimag(w),-creal(w));
	else
		return cpack(-cimag(w),creal(w));
}