setOutputFormat();
  public boolean inputFormat(Instances instanceInfo)        throws Exception {    super.inputFormat(instanceInfo);    m_AttIndex = m_AttIndexSet;    if (m_AttIndex < 0) {      m_AttIndex = instanceInfo.numAttributes() - 1;    }    m_FirstIndex = m_FirstIndexSet;    if (m_FirstIndex < 0) {      m_FirstIndex = instanceInfo.attribute(m_AttIndex).numValues() - 1;    }    m_SecondIndex = m_SecondIndexSet;    if (m_SecondIndex < 0) {      m_SecondIndex = instanceInfo.attribute(m_AttIndex).numValues() - 1;    }    if (!instanceInfo.attribute(m_AttIndex).isNominal()) {      throw new Exception("Chosen attribute not nominal.");    }    if (instanceInfo.attribute(m_AttIndex).numValues() < 2) {      throw new Exception("Chosen attribute has less than two values.");    }    return true;  }