barcat -e --markers=+/1 input/powers_of_ten.txt
     1 
    10 ----+-
   100 ----+-----+
  1000 ----+-----+----+-
   1e4 ----+-----+----+-----+
100000 ----+-----+----+-----+----+-
   1e6 ----+-----+----+-----+----+-----+