Returns the complex hyperbolic tangent of its argument.

    This function is supported on OpenVMS Integrity servers and
    Alpha only.

    Format

      #include  <complex.h>

      double complex ctanh  (double complex z);

      float complex ctanhf  (float complex z);

      long double complex ctanhl  (long double complex z);

1 - Argument

 z

    A complex value.

2 - Description

    The ctanh functions compute the complex hyperbolic tangent value
    of z.

3 - Return Values

    x                  The complex hyperbolic tangent value.