 10°  absolute XYZ tristimulus values or spectral data</span>
<span class="sd">            |  or color appearance attributes of stimulus</span>
<span class="sd">        :datab: </span>
<span class="sd">            | ndarray of CIE 2006 10°  absolute XYZ tristimulus values or spectral data</span>
<span class="sd">            |  of stimulus background</span>
<span class="sd">        :Lb: </span>
<span class="sd">            | [100], optional</span>
<span class="sd">            | Luminance (cd/m²) value(s) 