x="-1"></a>porto_aberdeen_func <span class="ot">&lt;-</span> <span class="fu">multiply_columns</span>(city<span class="sc">$</span>porto, city<span class="sc">$</span>aberdeen)</span>
<span id="cb404-2"><a href="loops.html#cb404-2" tabindex="-1"></a>i <span class="ot">&lt;-</span> <span class="dv">1</span></span>
<span id="cb404-3"><a href="loops.html#cb404-3" tabindex="-1"></a><span class="fu">identical</span>(<span class="fu">multiply_columns</span>(city[, i], city[, i <span class="sc">+</span> <span clas