docs: public void heldOutSetC(final GeneralDataset<L, F> trainSet, final GeneralDataset<L, F> devSet, final Scorer<L> scorer, LineSearcher minimizer) {
  
      useAlphaFile = true;
      boolean oldUseSigmoid = useSigmoid;
      useSigmoid = false;
  
      Function<Double,Double> negativeScorer =
        new Function<Double,Double> ()
        {
          public Double apply(Double cToTry) {
            C = cToTry;
            SVMLightClassifier<L, F> classifier = trainClassifierBasic(trainSet);
            double score = scorer.score(classifier,devSet);
            return -score;
          }
        };
  
      C = minimizer.minimize(negativeScorer);
  
      useAlphaFile = false;
      useSigmoid = oldUseSigmoid;
    }