>)</span> <span class="op">{</span></span></span>
<span class="r-in"><span><span class="va">theta1</span> <span class="op">&lt;-</span> <span class="va">theta</span><span class="op">[</span>,<span class="fl">1</span><span class="op">:</span><span class="fl">4</span>, drop <span class="op">=</span> <span class="cn">FALSE</span><span class="op">]</span></span></span>
<span class="r-in"><span><span class="va">theta2</span> <span class="op">&lt;-</span> <span class="va">theta</span><span class="op">[</span>,<sp