s here. This might be due to stringsAsFactors."</span>)</a>
<a class="sourceLine" id="cb31-2" title="2"><span class="co">#&gt; Error: Factors here. This might be due to stringsAsFactors.</span></a>
<a class="sourceLine" id="cb31-3" title="3"></a>
<a class="sourceLine" id="cb31-4" title="4"><span class="kw"><a href="reference/messagehandler.html">warn_if_none</a></span>(<span class="dv">1</span><span class="op">:</span><span class="dv">10</span>, <span class="op">~</span><span class="st"> </span>.x <span cla