       |   b*v    b*v     b*v   |    
          |      1      2       3  | 
          |                        | 
          |   c*w    c*w     c*w   |   
          |      1      2       3  | 
           -                      - 
     
   where a = 1/A, b = 1/B, and c = 1/C. 
     </PRE>
<h4><a name="Examples">Examples</a></h4>
<PRE>
 
   Suppose that you have a matrix m whose columns are orthogonal  
   and have non-zero norm (but not necessarily norm 1).  Then the  
   routine <b>invort_c</b> can be used t