class IndexSorter {

    public static <T> IntSeries sortIndex(Series<T> s, Comparator<? super T> comparator) {
        int[] mutableIndex = IndexSorter.rowNumberSequence(s.size());
        IntComparator intComparator =  (i1, i2) -> comparator.compare(s.get(i1), s.get(i2));
        IntTimSort.sort(mutableIndex, intComparator);
        return new IntArraySeries(mutableIndex);
    }

    public  IndexSorter(DataFrame dataFrame);
    public  IndexSorter(DataFrame dataFrame, IntSeries rangeToSort);

}