[Mpi-comments] Error in MPI_Neighbor_alltoallw example?

[Timothy Brown]

Ah, perfect thanks! I didn't know about the trac/ticket system. 

Tim

> On Dec 5, 2014, at 9:04 AM, Rajeev Thakur <thakur at mcs.anl.gov> wrote:
> 
> Yes, see https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/420
> 
> Rajeev
> 
> 
> On Dec 5, 2014, at 9:41 AM, Timothy Brown <Timothy.Brown-1 at Colorado.EDU> wrote:
> 
>> Hello.
>> 
>> I was trying to use MPI_Neighbor_alltoallw() and was following the example on page 333 of the MPI-3.0 standard. However I believe the send and receive counts are incorrect. Lines 21 to 25:
>> 
>> DO i=1,num_neigh
>> sndcounts(i) = 100
>> rcvcounts(i) = 100
>> rcvtypes(i)  = sndtypes(i)
>> END DO
>> 
>> Since the send/receive counts for 1 and 2 are vectors types of length 100, we should be sending/receiving only 1 type/element. As follows:
>> 
>> sndcounts(1) = 1
>> sndcounts(2) = 1
>> sndcounts(3) = 100
>> sndcounts(4) = 100
>> 
>> rcvcounts = sndcounts
>> 
>> Indeed if I compile the example as per the standard, I get data corruption.
>> 
>> I couldn't find this in the errata published on May 14, 2014.  However if it is a known mistake please ignore my comment. 
>> 
>> Regards
>> Timothy Brown
>> _______________________________________________
>> mpi-comments mailing list
>> mpi-comments at lists.mpi-forum.org
>> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi-comments
> 
> _______________________________________________
> mpi-comments mailing list
> mpi-comments at lists.mpi-forum.org
> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi-comments