M578 - Alexiades
                      Lab 4
          Parallelizing your serial 1D code from Lab3

1. The outline_MPI file contains the basic MPI function syntax and an outline 
    of how they are used.  Read it !

2. Here are detailed  steps for parallelizing your serial code 
    Read ALL OF IT to see the whole story (and may want to print it out).

3. Then start doing, step by step, on a coarse mesh, MM=4 or 8.
    Stick to the instructions, variable names...  you can be creative later...
    Your parallelized code should produce identical results with your serial code! 
    Try MM = 64, 128, 256, 512, ...   on  nWRs = 2 , 4 , 8 , ...

4. When it does, submit: 
   a. max errors from a run with MM=256 (dx=1/256)  on  nWRs= 4 workers.

   b. timing on 2 and 4 and 8 workers (value of "MR timing" from each run), don't expect speed-up!  
   c. lab4.zip  with ONLY the essential files of your code 
                       (z.* , Makefile , dat)

There are many things involved, many things can go wrong...
...nobody said parallelizing is easy...
...But once you get it working, next time will be a breeze (relatively speaking...)!
Try to get it right the first time... debugging is very hard...
               !!! GOOD LUCK !!!