   v₂  0   0   0 ⎥</span>
<span class="co">#&gt;            ⎢                          ⎥</span>
<span class="co">#&gt;            ⎢0   0   0   0   w₂  0   0 ⎥</span>
<span class="co">#&gt;            ⎢                          ⎥</span>
<span class="co">#&gt;            ⎢0   0   0   0   0   w₂  0 ⎥</span>
<span class="co">#&gt;            ⎢                          ⎥</span>
<span class="co">#&gt;            ⎣0   0   0   0   0   0   w₂⎦</span>
<span class="va">L2inv</span> <s