private void displayPRF(String prefixStr, int correct, int guessed, int gold, int exact, int total, PrintWriter pw) {
      double precision = (guessed > 0 ? correct / (double) guessed : 1.0);
      double recall = (gold > 0 ? correct / (double) gold : 1.0);
      double f1 = (precision > 0.0 && recall > 0.0 ? 2.0 / (1.0 / precision + 1.0 / recall) : 0.0);
      
      double exactMatch = exact / (double) total;

      String displayStr = " P: " + ((int) (precision * 10000)) / 100.0 + " R: " + ((int) (recall * 10000)) / 100.0 + " F1: " + ((int) (f1 * 10000)) / 100.0 + " EX: "+((int) (exactMatch * 10000)) / 100.0 ;
      if (precision==0 || recall==0 || f1 == 0){
      	errorNum++;
      }
      pw.println(prefixStr+displayStr);
    }