n> <span class="o">+</span> <span class="n">bt</span><span class="o">**</span><span class="mi">2</span><span class="p">)</span>
    <span class="c1">#ht = cam.hue_angle(at,bt,htype = &#39;rad&#39;)</span>
    
    <span class="n">Lr</span> <span class="o">=</span> <span class="n">labr</span><span class="p">[</span><span class="o">...</span><span class="p">,</span><span class="mi">0</span><span class="p">:</span><span class="mi">1</span><span class="p">]</span>
    <span class="n">ar</span> <span class="o">=