docs: public double[][] getClassDistsResultingFromBinarySplit(double splitValue) {
          DoubleVector lhsDist = new DoubleVector();
          DoubleVector rhsDist = new DoubleVector();
          for (int i = 0; i < this.attValDistPerClass.size(); i++) {
              GreenwaldKhannaQuantileSummary estimator = this.attValDistPerClass.get(i);
              if (estimator != null) {
                  long countBelow = estimator.getCountBelow(splitValue);
                  lhsDist.addToValue(i, countBelow);
                  rhsDist.addToValue(i, estimator.getTotalCount() - countBelow);
              }
          }
          return new double[][]{lhsDist.getArrayRef(), rhsDist.getArrayRef()};
      }