ex_Entries<br></a>
             </small>
            </td>
          </tr>
        </tbody>
</table>

<h4><a name="Procedure">Procedure</a></h4>
<PRE>
   SpiceDouble halfpi_c ( void ) 

</PRE>
<h4><a name="Abstract">Abstract</a></h4>
<PRE>
 
   Return half the value of pi (the ratio of the circumference of 
   a circle to its diameter). 
 </PRE>
<h4><a name="Required_Reading">Required_Reading</a></h4>
<PRE>
 
   None. 
 </PRE>
<h4><a name="Keywords">Keywords</a></h4>
<PRE>
 
   CONSTANTS 
 

</PRE>
<h4><a n