resolution is missing in fibre neutron diffraction files

modules/io/src/mol/mmcif_reader.cc

@@ -761,9 +761,12 @@ void MMCifParser::ParseExptl(const std::vector<StringRef>& columns)
 
 void MMCifParser::ParseRefine(const std::vector<StringRef>& columns)
 {
+  StringRef col=columns[indices_[LS_D_RES_HIGH]];
+  if (col.size()!=1 || (col[0]!='?' && col[0]!='.')) {
     info_.SetResolution(this->TryGetReal(columns[indices_[LS_D_RES_HIGH]],
                                          "refine.ls_d_res_high"));
   }
+}
 
 void MMCifParser::ParsePdbxStructAssembly(const std::vector<StringRef>& columns)
 {