Usage: python nletcount.py [options] filename

Options:
  --version             show program's version number and exit
  -h, --help            show this help message and exit
  -s, --single-char-frequencies
                        Display single character frequencies
  -g, --graph-display   Display graphs (requires matplotlib and numpy)
  -n, --normalized      Display graphs normalized (-g or --graph-display must
                        be set)
  -w WINDOW_WIDTH, --window-width=WINDOW_WIDTH
                        Tally counts of window_width lengthed substrings.
  -f FILT, --filter=FILT
                        Show only counts that contain filt.
  -p POS, --pos=POS     Require that the filt character specified with -f or
                        --filter be at the pos'th position.