pan> <span class="o">=</span> <span class="n">mat</span><span class="p">[</span><span class="n">hdim</span><span class="p">:</span><span class="n">dim</span><span class="p">,</span> <span class="n">hdim</span><span class="p">:</span><span class="n">dim</span><span class="p">]</span>

                <span class="c1"># print(&#39;mat\n&#39;, mat)</span>
                <span class="c1"># print(&#39;x11\n&#39;, x11)</span>
                <span class="c1"># print(&#39;x12\n&#39;, x12)</span>
                <