The user must specify a communicator
upon creation of any TAO objects (such as a vector, matrix, or solver)
to indicate the processors over which the object is to be distributed.
For example, some commands for matrix, vector, and solver creation
are:
info = MatCreate(MPI_Comm comm,int m,int n,int M,int N,Mat *H); info = VecCreate(MPI_Comm comm,int m,int M,Vec *x); info = TaoCreate(MPI_Comm comm,TaoMethod method,TAO_SOLVER *tao);The creation routines are collective over all processors in the communicator; thus, all processors in the communicator must call the creation routine. In addition, if a sequence of collective routines is being used, the routines must be called in the same order on each processor.