ass="op">&lt;-</span> <span class="va">DT</span><span class="op">[</span>, <span class="fu">.</span><span class="op">(</span><span class="va">mcid</span>, <span class="va">start</span><span class="op">)</span><span class="op">]</span></span>
<span><span class="va">DT</span></span>
<span><span class="co">#&gt;                  mcid  start</span></span>
<span><span class="co">#&gt;                &lt;char&gt; &lt;char&gt;</span></span>
<span><span class="co">#&gt;     1: MCID3111142689 090401</span></span>
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