</p>
            </td>
</tr>
<tr>
<td>
              <p>
                half_pi
              </p>
            </td>
<td>
              <p>
                π/2
              </p>
            </td>
<td>
              <p>
                1.570796
              </p>
            </td>
<td>
              <p>
                Equivalent to POSIX constant M_PI2
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                third_pi
              </p>
            </td>
<td>
              <p