de><span class="r-in"><span><span class="co">################################</span></span></span>
<span class="r-in"><span><span class="co">######### example 1 ############</span></span></span>
<span class="r-in"><span><span class="co">################################</span></span></span>
<span class="r-in"><span></span></span>
<span class="r-in"><span><span class="va">main</span> <span class="op">&lt;-</span>  <span class="va">ptsd_cor1</span><span class="op">[</span><span class="fl">1</span><span class="