ss="name" /><col class="desc" /></colgroup>
    <tr>
      <th>x</th>
      <td><p>A data frame containing at least one variable of class <code>Date</code>,
<code>POSIXct</code> or <code>POSIXlt</code>.</p></td>
    </tr>
    <tr>
      <th>interval</th>
      <td><p>The interval of the returned datetime variable.
Any character string that would be accepted by <code><a href='https://www.rdocumentation.org/packages/base/topics/seq.Date'>seq.Date()</a></code> or
<code>seq.POSIXt</code>. When NULL the
the inte