Return names of all parmaeters.
| 201 | |
| 202 | /// Return names of all parmaeters. |
| 203 | const vector<string> param_names() { |
| 204 | vector<string> pname; |
| 205 | for (const auto& spec : param_specs_) pname.push_back(spec.name()); |
| 206 | return pname; |
| 207 | } |
| 208 | |
| 209 | /// Return the 'i'-th parameter name. |
| 210 | const string& param_name(size_t i) { |