ndims, icompname_ptrs.data(), nlevels,

                             2 * ndims, icompname_ptrs.data(), ncomps_total,

          ierr =
              DBPutMrgvar(metafile.get(), extentsname.c_str(), "mrgTree", ndims,
                          compname_ptrs.data(), nlevels, regionname_ptrs.data(),
                          DB_INT, data_ptrs.data(), nullptr);

          ierr = DBPutMrgvar(metafile.get(), extentsname.c_str(), "mrgTree",
                             2 * ndims, compname_ptrs.data(), ncomps_total,
                             regionname_ptrs.data(), DB_DOUBLE,
                             data_ptrs.data(), nullptr);

          const int rank = ndims;
          const int *const rank_ptr = &rank;

          const vector<int> ranks(ncomps_total, ndims);
          const vector<const void *> rank_ptrs{ranks.data()};

                             &rank_ptr, nullptr);

                             rank_ptrs.data(), nullptr);