QCD API(*)


	                          level 3                       
     -------------------------------------------------------------------------
     |             Dirac Operators, CG Routines etc.                          |
     |                                                                        |
     |           (Organized by MILC or SZIN or CPS etc.)                      |
     |                                                                        |
     ==========================================================================

     	                           level 2                                    
     --------------------------------------------------------------------------
     |                Data Parallel QCD Lattice Operations                    |
     |                 (overlapping Algebra and Messaging)                    |
     |                                                                        |
     |               A = SHIFT(B, mu) * C;  Global sums, etc                  |
     |                                                                        |
     --------------------------------------------------------------------------
     |  Lattice Wide Lin Alg          || Lattice Wide Data Movement           |
     |   (No Communication)           || (Pure Communiation, non-blocking)    |
     |                                ||                                      |
     |  e.g.   A = B * C              || e.g  Atemp = SHIFT(A, mu-dir)        |
     |                                ||                                      |
     ==========================================================================

                                    level 1 
     --------------------------------------------------------------------------
     | Single Site Linear Algebra API ||     Message Passing API              |
     |                                ||                                      |
     | SU(3), gamma algebra etc.      ||    (Know about mapping of Lattice    |
     |                                ||     into Network Geomentry)          |
     --------------------------------------------------------------------------


(*)Ideally each level only calls the level directly below it. When this is not
possible because of efficiency, this level structure should still be 
maintained in the SEMANTICS.

Rich Brower: Tue Jul 31 14:37:39 EDT 2001