+ } else if (serial == function_index_Derivative) {
+ // Inert derivative performs chain rule on the first argument only, and
+ // adds differentiation parameter to list (second argument)
+ GINAC_ASSERT(is_ex_exactly_of_type(seq[0], function));
+ GINAC_ASSERT(is_ex_exactly_of_type(seq[1], function));
+ ex fcn = seq[0];
+ ex arg_diff;
+ for (unsigned i=0; i!=fcn.nops(); i++) {
+ arg_diff = fcn.op(i).diff(s);
+ if (!arg_diff.is_zero()) {
+ lst new_lst = ex_to_lst(seq[1]);
+ new_lst.append(i);
+ result += arg_diff * Derivative(fcn, new_lst);
+ }
+ }