the 
   input window. If the new interval overlaps any of the intervals 
   in the window, the intervals are merged. Thus, the cardinality 
   of the input window can actually decrease as the result of an 
   insertion. However, because inserting an interval that is 
   disjoint from the other intervals in the window can increase the 
   cardinality of the window, the routine signals an error. 
 
   No other CSPICE unary window routine can increase the number of
   intervals in the input window.
</PRE>
<h4>