="fl">11</span><span class="op">]</span> <span class="op">-</span> <span class="fl">2</span> <span class="op">*</span> <span class="va">x</span><span class="op">[</span>,<span class="fl">12</span><span class="op">]</span><span class="op">^</span><span class="fl">2</span> <span class="op">+</span> <span class="va">x</span><span class="op">[</span>,<span class="fl">13</span><span class="op">]</span></span>
<span class="r-in"><span class="va">xbeta</span> <span class="op">&lt;-</span> <span class="va">xbeta</s