Classes for virtual topologies

public class Cartcomm extends Intracomm {

  public Object clone() { ... }

  // Topology Constructors

  static public Dims_create(int nnodes, int [] dims)
                                            throws MPIException {...}

  public CartParms Get() throws MPIException {...}

  public int Rank(int [] coords) throws MPIException {...}

  public int [] Coords(int rank) throws MPIException {...}

  public ShiftParms Shift(int direction, int disp) throws MPIException {...}

  public Cartcomm Sub(boolean [] remainDims) throws MPIException {...}

  public int Map(int [] dims, boolean [] periods) throws MPIException {...}
}

public class CartParms {

  // Return type for Cartcomm.get()

  public int [] dims ;
  public booleans [] periods ;
  public int [] coords ; 
}

public class ShiftParms {

  // Return type for Cartcomm.shift()

  public int rankSource ;
  public int rankDest ; 
}

public class Graphcomm extends Intracomm {

  public Object clone() { ... }

  // Topology Constructors

  public GraphParms Get() throws MPIException {...}

  public int [] Neighbours(int rank) throws MPIException {...}

  public int Map(int [] index, int [] edges) throws MPIException {...}
}

public class GraphParms {

  // Return type for Graphcomm.get()

  public int [] index ;
  public int [] edges ; 
}