Creating Groups

All group creation routines create a group by specifying the members to take from an existing group.

• MPI_Group_incl specifies specific members
• MPI_Group_excl excludes specific members
• MPI_Group_range_incl and MPI_Group_range_excl use ranges of members
• MPI_Group_union and MPI_Group_intersection creates a new group from two existing groups.

MPI_Comm_group( oldcomm, &group ); 

MPI_Group_free( &group );