gatherv.java

MPI for java for Distributed Programming

package mpi.ccl;
/*
 MPI-Java version :
    Sang Lim ([e-mail])
    Northeast Parallel Architectures Center at Syracuse University
    12/1/98
*/
import mpi.*;
 
public class gatherv {
  static public void main(String[] args) throws MPIException {
  }

  public gatherv() {
  }

  public gatherv(String[] args) throws Exception {
    
    final int MAXLEN = 10;
 
    int root,i,j,k;
    int myself,tasks,stride=15;
 
    MPI.Init(args);
    myself = MPI.COMM_WORLD.Rank();
    tasks = MPI.COMM_WORLD.Size();

    if(tasks > 8) {
      if(myself == 0) 
        System.out.println("gatherv must run with less than 8 tasks");

      MPI.Finalize();
      return;
    }

    int out[] = new int[MAXLEN];
    int in[]  = new int[MAXLEN*stride*tasks];
    int dis[] = new int[MAXLEN];
    int rcount[] = new int[MAXLEN];
    int ans[] = {1, 1, 1, 1, 1, 1, 1,1, 1, 1, 0,0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};

    for (i = 0; i<MAXLEN;i++){
       dis[i] = i*stride;
       rcount[i] = 5;
       out[i] = 1;
    }
    rcount[0] = 10;

    for (i = 0; i<MAXLEN*tasks*stride;i++){
       in[i] = 0;
    }
    
    if (myself == 0)
       MPI.COMM_WORLD.Gatherv(out,0,10,MPI.INT,
                              in ,0,rcount,dis,MPI.INT,0);
    else 
       MPI.COMM_WORLD.Gatherv(out,0,5,MPI.INT,
                              in ,0,rcount,dis,MPI.INT,0);

/*
    if(myself==0){
       for(i=0; i<tasks*stride; i++)
         if (ans[i]!=in[i])
             System.out.println("recived data : "+in[i]+"at ["+i+
	                        "] should be : "+ans[i]);
    }
*/
    
    MPI.COMM_WORLD.Barrier();
    if(myself == 0)  System.out.println("Gatherv TEST COMPLETE");
    MPI.Finalize();
  }
}