+static ex tanh_real_part(const ex & x)
+{
+ ex a = GiNaC::real_part(x);
+ ex b = GiNaC::imag_part(x);
+ return tanh(a)/(1+power(tanh(a),2)*power(tan(b),2));
+}
+
+static ex tanh_imag_part(const ex & x)
+{
+ ex a = GiNaC::real_part(x);
+ ex b = GiNaC::imag_part(x);
+ return tan(b)/(1+power(tanh(a),2)*power(tan(b),2));
+}
+