ofiles=()
  
  ofile="${opref}-sab.cts"
  echo "writing ${ofile} ..."
  cat ${ifile} \
    | compute_sab_counts.sh \
    > ${ofile}
  ofiles+=( ${ofile} )
   
  for let in "${letBs[@]}"; do 
  
    alet=$( n063_pinyin_to_ascii.sh "${let}" )
    
    ofile="${opref}-dnoc-${alet}.cts"
    echo "writing ${ofile} ..."
    cat ${ifile} \
      | compute_dnoc_counts.sh "${let}" \
      > "${ofile}"
    ofiles+=( ${ofile} )
  done

  wd=$(( ${#ofiles[@]} * 15 ))  
  pr -w${wd} -m -t -s'|' "${ofiles[@]}" | expand > ${opref}-dnoc-all.txt