Procedure

   void ucrss_c ( ConstSpiceDouble   v1[3],
                  ConstSpiceDouble   v2[3], 
                  SpiceDouble        vout[3] ) 

Abstract

 
   Compute the normalized cross product of two 3-vectors. 
 

Required_Reading

 
   None. 
 

Keywords

 
   VECTOR 
 

Brief_I/O

 
   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|. 
 

Detailed_Input

 
   v1   A 3-vector. 
 
   v2   A 3-vector. 
 

Detailed_Output

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

Parameters

 
   None. 
 

Exceptions

 
   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. 
 

Files

 
   None. 
 

Particulars

 
   None. 
 

Examples

 
   To get a unit normal to the plane spanned by two vectors 
   v1 and v2. Simply call 
 
       ucrss_c ( v1, v2, normal );
 

Restrictions

 
   None. 
 

Literature_References

 
   None 
 

Author_and_Institution

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

Version

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

      Made input vectors const.
      
   -CSPICE Version 1.0.0, 08-FEB-1998   (EDW)

Index_Entries

 
   unitized cross product 
 

Link to routine ucrss_c source file ucrss_c.c