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Group Management

int Group.size()
returns: number of processors in the group



Size of group. Java binding of the MPI operation MPI_GROUP_SIZE.

int Group.rank()
returns: rank of the calling process in the group



Rank of this process in group. Java binding of the MPI operation MPI_GROUP_RANK. Result value is MPI.UNDEFINED if this process is not a member of the group.

int [] Group.translateRanks(Group group1, int [] ranks1)
group1 another group
ranks1 array of valid ranks in group1
   
returns: array of corresponding ranks in this group



Translate ranks within another group to ranks within this group. Java binding of the MPI operation MPI_GROUP_TRANSLATE_RANKS. Result elements are MPI.UNDEFINED where no correspondence exists.

static int Group.compare(Group group1, Group group2)
group1 first group
group2 second group
   
returns: result



Compare two groups. Java binding of the MPI operation MPI_GROUP_COMPARE. MPI.IDENT results if the group members and group order are exactly the same in both groups. MPI.SIMILAR results if the group members are the same but the order is different. MPI.UNEQUAL results otherwise.

Group Comm.group()
returns: group corresponding to this communicator



Return group associated with a communicator. Java binding of the MPI operation MPI_COMM_GROUP.

static Group Group.union(Group group1, Group group2)
group1 first group
group2 second group
   
returns: union group



Set union of two groups. Java binding of the MPI operation MPI_GROUP_UNION.

static Group Group.intersection(Group group1, Group group2)
group1 first group
group2 second group
   
returns: intersection group



Set intersection of two groups. Java binding of the MPI operation MPI_GROUP_INTERSECTION.

static Group Group.difference(Group group1, Group group2)
group1 first group
group2 second group
   
returns: difference group



Result contains all elements of the first group that are not in the second group. Java binding of the MPI operation MPI_GROUP_DIFFERENCE.

Group Group.incl(int [] ranks)
ranks ranks from this group to appear in new group
   
returns: new group



Create a subset group including specified processes. Java binding of the MPI operation MPI_GROUP_INCL.

Group Group.excl(int [] ranks)
ranks ranks from this group not to appear in new group
   
returns: new group



Create a subset group excluding specified processes. Java binding of the MPI operation MPI_GROUP_EXCL.

Group Group.rangeIncl(int [] [] ranges)
ranges array of integer triplets
   
returns: new group



Create a subset group including processes specified by strided intervals of ranks. Java binding of the MPI operation MPI_GROUP_RANGE_INCL. The triplets are of the form $(\mbox{first rank}, \mbox{last rank},
\mbox{stride})$ indicating ranks in this group to be included in the new group. The size of the first dimension of ranges is the number of triplets. The size of the second dimension is 3.

Group Group.rangeExcl(int [] [] ranges)
ranges array of integer triplets
   
returns: new group



Create a subset group excluding processes specified by strided intervals of ranks. Java binding of the MPI operation MPI_GROUP_RANGE_EXCL. Triplet array is defined as for rangeIncl, the ranges indicating ranks in this group to be excluded from the new group.

void Group.finalize()
Destructor. Java binding of the MPI operation MPI_GROUP_FREE.


next up previous contents
Next: Communicator Management Up: Groups, Contexts and Communicators Previous: Basic Concepts   Contents
Bryan Carpenter 2002-07-12