ts, year:day)</code> and
<code>select_dt(flights, -(year:day))</code> are not supported. But I
have added a feature to help select with regular expression, which means
you can:</p>
<div class="sourceCode" id="cb6"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="../reference/select.html">select_dt</a></span><span class="op">(</span><span class="va">flights</span>, <span class="st">"^dep"</span><span class="op">)</span></span></code></pre></div>
<p>The rename proc