From: Bjorn Sjogreen <bjorns@nada.kth.se>
Newsgroups: comp.parallel.mpi
Subject: MPI_REDUCE
Date: Mon, 11 Jan 1999 11:53:06 +0100
Message-Id: <3699D811.B75AE147@nada.kth.se>
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Hello!

 I can not find anywhere in the standard document, whether a call to
MPI_Allreduce (or Reduce) with
 the same variable as both input and output buffer will give the
expected result. For example
what does the standard say about the following call
              MPI_Allreduce(   buf, buf, n, MPI_DOUBLE, MPI_MAX, comm )

?

regards

Bjorn Sjogreen

KTH, Stockholm, Sweden