code: public RVFDataset<L,F> getL1NormalizedTFIDFDataset(){
      RVFDataset<L,F> rvfDataset = new RVFDataset<L,F>(this.size(),this.featureIndex,this.labelIndex);
      Counter<F> featureDocCounts = getFeatureCounter();
      for(int i = 0; i < this.size(); i++){
        Datum<L,F> datum = this.getDatum(i);
        RVFDatum<L,F> rvfDatum = getL1NormalizedTFIDFDatum(datum,featureDocCounts);
        rvfDataset.add(rvfDatum);
      }
      return rvfDataset;
    }
docs: Method to convert this dataset to RVFDataset using L1-normalized TF-IDF features
  @return RVFDataset