 values (`stat_boxplot()`).</span>
<span class="r-plt img"><img src="gr_plot_periods-3.png" alt="" width="960" height="593"></span>
<span class="r-in"><span></span></span>
<span class="r-in"><span><span class="co"># use matrix layout to plot multiple variables</span></span></span>
<span class="r-in"><span><span class="fu">gr_plot_periods</span><span class="op">(</span><span class="va">vars</span>, <span class="va">Qygr</span>, <span class="va">Qspmax</span>, <span class="va">D10w1</span>, <span class="va">W