}
-unsigned zeta1_SERIAL::serial = function::register_new(function_options("zeta").
+unsigned zeta1_SERIAL::serial = function::register_new(function_options("zeta", 1).
evalf_func(zeta1_evalf).
eval_func(zeta1_eval).
derivative_func(zeta1_deriv).
}
-unsigned zeta2_SERIAL::serial = function::register_new(function_options("zeta").
+unsigned zeta2_SERIAL::serial = function::register_new(function_options("zeta", 2).
evalf_func(zeta2_evalf).
eval_func(zeta2_eval).
derivative_func(zeta2_deriv).