/span></code></pre></div>
<p><img src="introduction_files/figure-html/unnamed-chunk-7-1.png" width="700"></p>
<p>The grouping aesthetic does not need to be provided if a categorical
variable is mapped onto the y axis, but it does need to be provided if
the variable is numerical.</p>
<div class="sourceCode" id="cb7"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="co"># modified dataset that represents species as a number</span></span>
<span><span class="va">iris_num</span> <s