docs: public T[] getQuantiles(final double[] fRanks) {
      if (isEmpty()) { return null; }
      ItemsAuxiliary<T> aux = null;
      @SuppressWarnings("unchecked")
      final T[] quantiles = (T[]) Array.newInstance(minValue_.getClass(), fRanks.length);
      for (int i = 0; i < fRanks.length; i++) {
        final double fRank = fRanks[i];
        if      (fRank == 0.0) { quantiles[i] = minValue_; }
        else if (fRank == 1.0) { quantiles[i] = maxValue_; }
        else {
          if (aux == null) {
            aux = this.constructAuxiliary();
          }
          quantiles[i] = aux.getQuantile(fRank);
        }
      }
      return quantiles;
    }