ss="fl">0</span>, <span class="fl">0</span>, <span class="fl">0</span><span class="op">)</span></span>
<span><span class="va">Z</span><span class="op">[</span>,<span class="fl">2</span><span class="op">]</span> <span class="op">&lt;-</span> <span class="va">X</span><span class="op">[</span>,<span class="fl">2</span><span class="op">]</span> <span class="op">-</span> <span class="fu"><a href="../reference/Proj.html">Proj</a></span><span class="op">(</span><span class="va">X</span><span class="op">[</span>,<s