/*D
   MPI_Comm_create_group - Creates a new communicator

Synopsis:
.vb
int MPI_Comm_create_group(MPI_Comm comm, MPI_Group group, int tag,
                          MPI_Comm *newcomm)
.ve

Input Parameters:
+ comm - intra-communicator (handle)
. group - group, which is a subset of the group of comm (handle)
- tag - tag (integer)

Output Parameters:
. newcomm - new communicator (handle)

.N ThreadSafe

.N Fortran

.N Errors
.N MPI_SUCCESS
.N MPI_ERR_ARG
.N MPI_ERR_COMM
.N MPI_ERR_GROUP
.N MPI_ERR_TAG
.N MPI_ERR_OTHER

.seealso: MPI_Comm_free
D*/

