"p">]):</span>
       
        <span class="c1"># get rho, gamma, beta of background and reference white:</span>
        <span class="k">if</span> <span class="p">(</span><span class="n">inputtype</span> <span class="o">!=</span> <span class="s1">&#39;xyz&#39;</span><span class="p">):</span>
            <span class="n">xyzb</span> <span class="o">=</span> <span class="n">spd_to_xyz</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">vstack</span><span class="p">((<