cpp/numeric/complex/tanh

Computes complex hyperbolic tangent of a complex value.

Return value
If no errors occur, complex hyperbolic tangent of is returned.

Error handling and special values
Errors are reported consistent with math_errhandling.

If the implementation supports IEEE floating-point arithmetic,
 * If is, the result is
 * If is  (for any finite x), the result is  and fe_invalid is raised
 * If is  (for any finite x), the result is  and fe_invalid may be raised
 * If is  (for any finite positive y), the result is
 * If is, the result is  (the sign of the imaginary part is unspecified)
 * If is, the result is  (the sign of the imaginary part is unspecified)
 * If is, the result is
 * If is  (for any non-zero y), the result is  and fe_invalid may be raised
 * If is, the result is
 * If is  (for any non-zero y), the result is  and fe_invalid may be raised
 * If is, the result is