code: @Override
      public DataSet sample(int numSamples, org.nd4j.linalg.api.rng.Random rng) {
          return sample(numSamples, rng, false);
      }
docs: Sample without replacement
  
  @param numSamples the number of samples to getFromOrigin
  @param rng        the rng to use
  @return the sampled dataset without replacement