1. Purpose
This lab is intended to help you practice MPI Java. You are to code and run an MPI Java program that includes MPI.COMM_WORLD.Send( ) and MPI.COMM_WORLD.Recv( )
Statement of Work
Code an MPI java program that executes the following square root computation:
rank 0: creates an array of 100 "double" elements, (say, dArray[100]); sends dArray[25] through to dArray[49] to rank 1, dArray[50] through to dArray[74] rank 2, and dArray[75] through to dArray[99] to rank3. Then, it locally computes "sqrt" of dArray[0] through to dArray[24]; and finally receives the results from the other ranks. Use MPI.COMM_WORLD.Send( ) and MPI.COMM_WORLD.Recv( ) to send and receive an array with a remote rank. (Don't try to communicate with rank0 itself, which hangs up communication.) At the very end, print out all array elements.
other ranks: create an array of 25 "double" elements, (say, dArray[25]); receive data in dArray[0] through to dArray[24] from rank 0. Locally computes "sqrt" of all the array elements; and finally send the results to rank 0. Use MPI.COMM_WORLD.Recv( ) and MPI.COMM_WORLD.Send( ) to receive from and send an array to rank 0.
Make sure that you have set up your MPI execution envrionment first.
Compile and run your MPI java program by typing:
javac MyProgram.java
prunjava 4 MyProgram
NOTE: You may have to use the suggested script not_prunjava from lab2a
Related Material
The MPI slides
For details of MPI Java, refer to the following tutorial and specification.
http://www.hpjava.org/courses/arl/lectures/mpi.ppt
http://www.hpjava.org/reports/mpiJava-spec/mpiJava-spec.pdf
What to Turn in
Turn in the following materials in Canvas by the specified due date.
Your MPI java program, (i.e., MyProgram.java)
Your execution output, (i.e., output.txt)
