NULL, NULL, &natoms, xref, NULL, NULL, NULL);
calc_hxprops(nres, bb, xref);
do_start_end(nres, bb, &nbb, bbindex, &nca, caindex, bRange, rStart, rEnd);
NULL, NULL, &natoms, xref, NULL, NULL, NULL);
calc_hxprops(nres, bb, xref);
do_start_end(nres, bb, &nbb, bbindex, &nca, caindex, bRange, rStart, rEnd);