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Measurements of standard quantities such as energy and magnetization are
easily done in parallel.
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Calculate the quantities locally (e.g., energy per site),
which can be done completely in parallel (no checkerboarding required)
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Do a partial sum over sites in each processor
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Combine the partial sums on each processor, using for example
MPI_SUM in MPI.
In data parallel languages such as HPF, the last two steps can be
implemented using the SUM primitive. For example,
energy = SUM (energy-per-site) / volume
Paul Coddington, Northeast Parallel Architectures Center at Syracuse University, paulc@npac.syr.edu