l-link">rep</a></span><span class="op">(</span><span class="cn">NA</span>, <span class="fl">5</span><span class="op">)</span><span class="op">)</span> 

<span class="fu"><a href="https://rdrr.io/r/utils/head.html" class="external-link">head</a></span><span class="op">(</span><span class="fu"><a href="reference/drop_all_na.html">drop_all_na</a></span><span class="op">(</span><span class="va">test</span>, grouping_cols <span class="op">=</span> <span class="st">"ID"</span><span class="op">)</span><span class=