 <td>Voronoi cell constructor. </td>
          </tr>
          <tr>
            <td style="font-family: Courier New,Courier,monospace;">source_index_type
            <span style="font-weight: bold;">source_index</span>()
const </td>
            <td>Returns input site index among the other sites.<br>
Both segment and its end points will have the same index. </td>
          </tr>
          <tr>
            <td style="font-family: Courier New,Courier,monospace;">source_category_type
            <span style="fo