vector.java

MPI for java for Distributed Programming

package mpi.dtyp; 

import mpi.*;
import java.util.Arrays;

/**
 * This example application, is to check and demonstrate the functonality of contiguous datatypes. I'm writing an MPJ program by coverting a C program by Forest Hoffman at following URL
 * http://www.linux-mag.com/2003-04/extreme_01.html
 * 
 */ 
public class Vector {
	public static int NUM_PARAMS=1024;
	
    public static void main (String args[]) throws Exception{

    }

    public Vector() {
    }

    public Vector(String[] args) throws Exception {

	    

	    MPI.Init(args); 	    
	    int i, rank, size;
	    
	    double [] data = new double[NUM_PARAMS];	    
	    double [] rdata = new double[NUM_PARAMS];
	    
	    rank = MPI.COMM_WORLD.Rank();	    
	    size = MPI.COMM_WORLD.Size();
	    Datatype parameterType;

	    /* only the first process reads the parameters */
	    if(rank == 0) {
		    for(i=0 ; i<NUM_PARAMS ; i++) {
			   data[i]=(double) (i*i);
		    }
	    }

	    if (rank  == 1) {
		   
		    MPI.COMM_WORLD.Recv(rdata,0,64,MPI.DOUBLE,0,10);     
		    System.out.println("recv completed");

		    for(int j=0 ; j<10 ; j++) {
			    System.out.print("rdata["+j+"]="+rdata[j]+"\t");
		    }
		    
		    /* work out what would be test ? 
		    if (Arrays.equals(source,dest)) {
			    System.out.println("PASS");
		    }else {
			    System.out.println("\n****");
			    System.out.println("FAIL");
			    System.out.println("****");
		    }*/
	    }else if(rank == 0) {	 
		    parameterType = Datatype.Vector(64,1,16, MPI.DOUBLE);
		    parameterType.Commit();
		    MPI.COMM_WORLD.Send(data,0,1,parameterType,1, 10);
		    System.out.println("Send Completed");	    		   }
	    try { Thread.currentThread().sleep(1000); }catch(Exception e){}
	    MPI.COMM_WORLD.Barrier();
	    MPI.Finalize();
    }    
}