docs: @Override
    public void writeToText(TextWriterStream out, String label) {
      if(label != null) {
        out.commentPrintLn(label);
      }
      out.commentPrintLn("Model class: " + this.getClass().getName());
      try {
        if(getNormalizedLinearEquationSystem(null) != null) {
          // TODO: more elegant way of doing normalization here?
          /*
           * if(out instanceof TextWriterStreamNormalizing) {
           * TextWriterStreamNormalizing<V> nout =
           * (TextWriterStreamNormalizing<V>) out; LinearEquationSystem lq =
           * getNormalizedLinearEquationSystem(nout.getNormalization());
           * out.commentPrint("Linear Equation System: ");
           * out.commentPrintLn(lq.equationsToString(nf)); } else {
           */
          LinearEquationSystem lq = getNormalizedLinearEquationSystem(null);
          out.commentPrint("Linear Equation System: ");
          out.commentPrintLn(lq.equationsToString(nf));
          // }
        }
      }
      catch(NonNumericFeaturesException e) {
        LoggingUtil.exception(e);
      }
    }