df</span> <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/cbind.html" class="external-link">cbind</a></span><span class="op">(</span>id <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/rep.html" class="external-link">rep</a></span><span class="op">(</span><span class="fl">1</span><span class="op">:</span><span class="fl">10</span>, each <span class="op">=</span> <span class="fl">5</span><span class="op">)</span>,</span>
<span>            items <span class