asss <code>matrix</code>, it will be converted to a
<code>data.frame</code>.</p></td>
    </tr>
    <tr>
      <th>vol</th>
      <td><p>Extra text string or numeric that is appended on the end of the output
file name(s). For example, if the dataset is called "myData", no file argument is
 supplied and <code>vol=2</code>, the output file will be called "codebook_myData2.Rmd"</p></td>
    </tr>
    <tr>
      <th>reportTitle</th>
      <td><p>A text string. If supplied, this will be the printed title of the
