code: def _insert_to_array(self, chunk, results):
          
  
          ## two result arrs
          chunksize = self._chunksize
          qrts, invs = results
  
          ## enter into db
          with h5py.File(self.database.output, 'r+') as io5:
              io5['quartets'][chunk:chunk+chunksize] = qrts
  
              ## entered as 0-indexed !
              if self.params.save_invariants:
                  if self.checkpoint.boots:
                      key = "invariants/boot{}".format(self.checkpoint.boots)
                      io5[key][chunk:chunk+chunksize] = invs
                  else:
                      io5["invariants/boot0"][chunk:chunk+chunksize] = invs
docs: Enters results arrays into the HDF5 database.