Relation to <i>count</i>

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Relation to count


A call of the form MPI_SEND(buf, count, datatype , ...), where count > 1 , is interpreted as if the call was passed a new datatype which is the concatenation of count copies of datatype. Thus, MPI_SEND(buf, count, datatype, dest, tag, comm) is equivalent to,

MPI_TYPE_CONTIGUOUS(count, datatype, newtype)
MPI_SEND(buf, 1, newtype, dest, tag, comm).

Similar statements apply to all other communication functions that have a count and datatype argument.

Jack Dongarra
Fri Sep 1 06:16:55 EDT 1995