/** Inverse hyperbolic tangent \ingroup complex \param[in] z Complex number \return \f$ \mathrm{atanh} z \f$*/ complex arctanh(const complex& z) { return complex(gsl_complex_arctanh(z.as_gsl_type())); }
gsl_complex gsl_complex_arccoth(gsl_complex a) { /* z = arccoth(a) */ gsl_complex t = gsl_complex_inverse(a); return gsl_complex_arctanh(t); }
void gsl_complex_arccoth (complex_t const *a, complex_t *res) { /* z = arccoth(a); */ gsl_complex_inverse (a, res); gsl_complex_arctanh (res, res); }