src/main/java/org/helm/notation2/parser/notation/grouping/GroupingMixture.java
@Override
  public String toHELM2() {
    DecimalFormat d = new DecimalFormat("#.##");
    StringBuilder notation = new StringBuilder();
    for (GroupingElement groupingElement : elements) {
      if (!(groupingElement.isDefaultValue())) {
        String value = d.format(groupingElement.getValue().get(0)).replace(',', '.');
        if (groupingElement.getValue().size() > 1) {
          value += "-" + d.format(groupingElement.getValue().get(1)).replace(',', '.');
        }
        notation.append(groupingElement.getID() + ":" + value + "+");
      } else {
        notation.append(groupingElement.getID() + "+");
      }

    }

    notation.setLength(notation.length() - 1);

    return notation.toString();
  }
@Override
  public String toHELM2() {
    DecimalFormat d = new DecimalFormat("#.##");
    StringBuilder notation = new StringBuilder();
    for (GroupingElement groupingElement : elements) {
      if (!(groupingElement.isDefaultValue())) {
        String value = d.format(groupingElement.getValue().get(0)).replace(',', '.');
        if (groupingElement.getValue().size() > 1) {
          value += "-" + d.format(groupingElement.getValue().get(1)).replace(',', '.');
        }
        notation.append(groupingElement.getID() + ":" + value + "+");
      } else {
        notation.append(groupingElement.getID() + "+");
      }

    }

    notation.setLength(notation.length() - 1);

    return notation.toString();
  }
{@inheritDoc}