Request for clarification

Linda Stanberry (linda@k2.llnl.gov)
Mon, 9 Jun 1997 15:22:26 -0700 (PDT)

My interpretation of the filetype tiling (after corrections from previous
discussions here) is that holes at the beginning or end of a filetype
will be repeated in the filetype tiling only if explicit MPI_LB and
MPI_UB are used to set the extent appropriately to include the holes.

The words describing the tiling for the filetype in figure 10.1 only
mention the need for an MPI_LB to repeat the 1-unit hole at the beginning,
leaving me to wonder about how the 3-unit hole at the end is repeated.
(See page 216, the definition of view, in the May 8 text.)

In the example, with explicit MPI_LB and MPI_UB, I believe the extent of the
filetype is 6 units, and without, the extent is only 2 units. Thus to get
the tiling shown in the figure, I expect an MPI_UB would be needed.

Do others agree with this assessment? If not, can someone explain the
error in my reasoning?

Linda Stanberry
lstanberry@llnl.gov