Newsgroups: comp.parallel.mpi
From: L J Clarke <lyndon>
Subject: Re: Does MPI_REDUCE work for max & min Complex datatype?
Organization: EPCC
Date: Thu, 22 Jun 1995 08:54:00 GMT
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Message-ID: <DAKGq0.IEL@dcs.ed.ac.uk>

MPI_REDUCE for operations MPI_MIN and MPI_MAX and data type MPI_COMPLEX is not
defined in MPI. This is an error in the old draft which has now been fixed.

Incidentally, how would you expect the minimum and maximum of two complex
numbers to be defined? Perhaps you would have liked the number with the 
maximum (minimum) modulus. On the other hand perhaps the number with the
maximum (minimum) real component, or even the maximum (minimum) imaginary
component...

Cheers
Lyndon

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e||) Lyndon J Clarke    Edinburgh Parallel Computing Centre|                 |
c||c Tel: 0131 650 5021 Email: lyndon@epcc.edinburgh.ac.uk |                 |-
-----| URL: http://www.epcc.ed.ac.uk/~lyndon/              |                  
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