talic;">% plots the c=mean(signal) isosurface</span><br>&gt;&gt; <span style="color: rgb(51, 102, 255);">plot</span>(c,<span style="color: rgb(204, 51, 204);">'surf half'</span>);      <span style="font-style: italic;">% plots the c=(max-min)/2 isosurface</span><br>&gt;&gt; <span style="color: rgb(51, 102, 255);">plot</span>(c,<span style="color: rgb(204, 51, 204);">'plot3'</span>);          <span style="font-style: italic;">% plots a volume rendering with semi-transparent style</span>, same as <span style=