...gathering
The MPI call for gather is MPI_Gather.
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...scatter
The MPI call for scatter is MPI_Scatter.
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...collect
The MPI call for collect is MPI_Allgather.
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...broadcast
The MPI call for broadcast is MPI_Bcast.
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...template
Notice, our use of the word template should not be confused with the use of templates in C++.
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...global_length
To keep from being confused: once projected, the (multi)vector should be viewed as a special case of the matrix, which exists entirely within the row(s) or column(s) that own the projected vector. Thus, global_length and global_width reflect the length and width of the (multi)vector viewed as a matrix.
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...rank-k
Notice that the generic name for this operation is ``rank-k'' update. Since k is one of the dimensions of the matrices, we are really performing rank-s updates.
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...processor
For the Cray T3D and Convex Exemplar, the term node is somewhat confusing. A node board of a Cray T3D contains two processors (processing elements or PEs). A Convex Exemplar node consists of sixteen processors in a shared memory configuration. Notice that in our terminology, one node equals one Cray T3D PE or one Convex Exemplar processor.
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rvdg@cs.utexas.edu