plotTrainingData();
      public void actionPerformed(ActionEvent e) {        try {		setInstancesFromFileQ();		int classIndex = m_classAttBox.getSelectedIndex();		if (m_trainingInstances != null && m_classifier != null && (m_trainingInstances.attribute(classIndex).isNominal())) {			m_startBut.setEnabled(true);		}				plotTrainingData();	} catch (Exception ex) {		ex.printStackTrace(System.out);		System.err.println("exception");	}	      }