code: public String categoryAndFunction(String category) {
      if (category == null) {
        return null;
      }
      String catFunc = category;
      int i = lastIndexOfNumericTag(catFunc);
      while (i >= 0) {
        catFunc = catFunc.substring(0, i);
        i = lastIndexOfNumericTag(catFunc);
      }
      return catFunc;
    }
docs: Returns the syntactic category and 'function' of a String.
  This normally involves truncating numerical coindexation
  showing coreference, etc.  By 'function', this means
  keeping, say, Penn Treebank functional tags or ICE phrasal functions,
  perhaps returning them as <code>category-function</code>.
  <p/>
  This implementation strips numeric tags after label introducing
  characters (assuming that non-numeric things are functional tags).
  
  @param category The whole String name of the label
  @return A String giving the category and function