cal ROI contains&quot;</span>, <span class="fu">length</span>(sphere), <span class="st">&quot;voxels</span><span class="sc">\n</span><span class="st">&quot;</span>)</span>
<span id="cb4-4"><a href="#cb4-4" tabindex="-1"></a><span class="co">#&gt; Spherical ROI contains 11 voxels</span></span>
<span id="cb4-5"><a href="#cb4-5" tabindex="-1"></a></span>
<span id="cb4-6"><a href="#cb4-6" tabindex="-1"></a><span class="co"># Cuboid ROI - rectangular box</span></span>
<span id="cb4-7"><a href="#cb4-7" tabindex="