comm_test.java

来自「MPI for java for Distributed Programming」· Java 代码 · 共 62 行

package mpi.comm; 

import mpi.*;
import java.util.Arrays;
/*
 * things i have done today, 
 * 1. Intracomm class, createGroup method. Intracomm constructor. 
 * created this comm_test class
 * 2. was trying to make this stupid collective 
 * operations work. as their 
 * and the backup should be 20th Jan and get aamirmpj, 
 * the whole code now .... 
 */

public class comm_test {
  /* this test runs with eight processors at the moment. */
  public static void main (String args[]) throws Exception {
  }

  public comm_test() {
  }

  public comm_test(String[] args) throws Exception {
	  
    MPI.Init(args); 	    
    Group grp1 = MPI.COMM_WORLD.Group();
    Comm myComm;
    int[] incl1 = { 0, 2, 4, 6};
    int rank = MPI.COMM_WORLD.Rank();
    int size = MPI.COMM_WORLD.Size();
    
    if(size < 8) {
      if(rank == 0) 	    
        System.out.println("comm->comm_test: RUNS WITH 8 processes atleast");
  
      MPI.COMM_WORLD.Barrier();
      MPI.Finalize(); 
      return; 
    }

    Group grp2 = grp1.Incl(incl1);
    //System.out.println("world<"+rank+">,newComm<"+grp2.Rank()+">");

    /* i've to write this if statement because group methods 
     * return null 
     * at the moment, which results in nullpointer exception. 
     * this has to be 
     * fixed by returning EMPTY and other relevant flags 
     */
    
    if( rank== 0 || rank==2|| rank==4 || rank==6 ) {
      //System.out.println("rank "+rank+" is within");
      myComm = MPI.COMM_WORLD.Create(grp2);		   
    }     
    
    MPI.COMM_WORLD.Barrier();
    if(rank == 0) 
      System.out.println("comm_test TEST COMPLETE"); 	    
    MPI.Finalize();
}    
}