docs: private LinearEquationSystem runDerivator(Relation<ParameterizationFunction> relation, int dimensionality, DBIDs ids) {
      try {
        // build database for derivator
        Database derivatorDB = buildDerivatorDB(relation, ids);
  
        PCARunner pca = new PCARunner(new StandardCovarianceMatrixBuilder());
        EigenPairFilter filter = new FirstNEigenPairFilter(dimensionality);
        DependencyDerivator<DoubleVector> derivator = new DependencyDerivator<>(null, FormatUtil.NF4, pca, filter, 0, false);
  
        CorrelationAnalysisSolution<DoubleVector> model = derivator.run(derivatorDB);
        LinearEquationSystem les = model.getNormalizedLinearEquationSystem(null);
        return les;
      }
      catch(NonNumericFeaturesException e) {
        throw new IllegalStateException("Error during normalization" + e);
      }
    }