Compute the normalized cross product of two 3-vectors. 

   None. 

   VARIABLE  I/O  DESCRIPTION 
   --------  ---  -------------------------------------------------- 
   v1         I     Left vector for cross product. 
   v2         I     Right vector for cross product. 
   vout       O     Normalized cross product (v1xv2) / |v1xv2|. 

   v1   A 3-vector. 

   v2   A 3-vector. 

   vout is the result of the computation (v1xv2)/|v1xv2| 

   None. 

   None. 

   To get a unit normal to the plane spanned by two vectors 
   v1 and v2. Simply call 

       ucrss_c ( v1, v2, normal );

   None. 

   Error free. 

   1) If the cross product of v1 and v2 yields the zero-vector, then 
      the zero-vector is returned instead of a vector of unit length. 

   None. 

   W.M. Owen       (JPL) 
   W.L. Taber      (JPL) 

   None 

   -CSPICE Version 1.1.0, 22-OCT-1998 (NJB)

      Made input vectors const.

   -CSPICE Version 1.0.0, 08-FEB-1998   (EDW)

   unitized cross product