[Mpi-forum] Handling of MPI_BOTTOM in Reductions

[Marc-André Hermanns]

Hi all,

I have a question on the use of MPI_BOTTOM for the following function 
calls: 

MPI_Reduce
MPI_Reduce_scatter
MPI_Scan
MPI_Exscan
MPI_Reduce_local
MPI_Reduce_scatter_block

They only have a single datatype, but two buffers. With MPI_BOTTOM as 
the  address of the buffer is encoded in the datatype. As I only have 
a single datatype, does MPI_BOTTOM imply MPI_IN_PLACE as the other
argument?  

Cheers,
Marc-Andre
--
Marc-Andre Hermanns
German Research School for
Simulation Sciences GmbH
c/o Laboratory for Parallel Programming
52056 Aachen | Germany

Tel +49 241 80 99753
Fax +49 241 80 6 99753
Web www.grs-sim.de

Members: Forschungszentrum Jülich GmbH | RWTH Aachen University
Registered in the commercial register of the local court of
Düren (Amtsgericht Düren) under registration number HRB 5268
Registered office: Jülich
Executive board: Prof. Marek Behr Ph.D. | Dr. Norbert Drewes

-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 4427 bytes
Desc: not available
URL: <http://lists.mpi-forum.org/pipermail/mpi-forum/attachments/20101007/ead5b963/attachment.bin>