PATH=./:$PATH
if [[ -z $2 ]]; then
  echo -e "Incorrect call of mktree. Expected:\n  mktree filename output-format [options]"
elif [[ ! -e $1 ]]; then
  echo "Incorrect call of mktree – file '$1' does not exist."
else
  x=$(basename $1) && x=$(dirname $1)/${x%.*}.$2
  opt=$3
  if [[ ! $opt =~ ^.*[in].*$ ]]; then
    (ttdot $opt | neato -y -n -Tdot | neato -n -T$2) <$1 >$x
  elif [[ $opt =~ ^.*n.*$ ]]; then
    opt=${opt/n}
    if [[ $opt =~ ^.*i.*$ ]]; then       # ni
      opt=${opt/i}
      (ttdot $opt | dot -Tdot | neato -y -n -Tdot | neato -n -T$2) <$1 >$x
    else                                 # n
      (ttdot $opt | dot -T$2) <$1 >$x
    fi
  else                                   # i
    opt=${opt/i}
    (ttdot $opt | neato -n -T$2) <$1 >$x
  fi
fi