newlib/winsup/mingw/mingwex/complex/ctanhl.c

45 lines
823 B
C
Executable File

/* ctanhl.c */
/*
Contributed by Danny Smith
2005-01-04
*/
#include <math.h>
#include <complex.h>
#include <errno.h>
/*
ctanh (x + I * y) = (sinh (2 * x) + sin (2 * y) * I )
/ (cosh (2 * x) + cos (2 * y)) .
*/
long double complex
ctanhl (long double complex Z)
{
long double complex Res;
long double two_R = 2.0L * __real__ Z;
long double two_I = 2.0L * __imag__ Z;
long double denom = coshl (two_R) + cosl (two_I);
if (denom == 0.0L)
{
errno = ERANGE;
__real__ Res = HUGE_VALL;
__imag__ Res = HUGE_VALL;
}
else if (isinf (denom))
{
errno = ERANGE;
__real__ Res = two_R > 0 ? 1.0L : -1.0L;
__imag__ Res = 0.0L;
}
else
{
__real__ Res = sinhl (two_R) / denom;
__imag__ Res = sinl (two_I) / denom;
}
return Res;
}