   <a href="spkez_c.html">spkez_c</a> ( IO, et, &quot;J2000&quot;, &quot;lt&quot;, VG2, state, &amp;lt );

         <a href="vequ_c.html">vequ_c</a>  ( state, pos2 );

         /.
         Call <b>vrel_c</b> to find the relative difference between the
         two states.
         ./
         diff = <b>vrel_c</b> ( pos1, pos2 );

         .
         .
         .
</PRE>
<h4><a name="Restrictions">Restrictions</a></h4>
<PRE>
   None.
</PRE>
<h4><a name="Literature_References">Literature_References</a></h4>
<P