ing data,
and <code>"na.fail"</code> which fails if there is missing data.
See <code>link[stats]{na.pass}()</code> and <code><a href="na.warn.html">na.warn()</a></code> for details.
The default is <code>"na.warn"</code> unless no function are specified in <code>...</code>, in which case
<code>"na.pass"</code> is used since the default function reports the number of missing values.</p></dd>

</dl></div>
    <div id="value">
    <h2>Value</h2>
    

<p>A data frame. Names of columns in the resulting data fram