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PLAPACK calls

The PLAPACK equivalent local and global level-3 BLAS calls are given by place HR here

figure9619

figure9623

figure9626

place HR here Parameters UPLO and TRANS have been replaced by integer parameters uplo and trans, which can take on the values indicated in Table gif. All other parameters are now passed as part of linear algebra objects alpha, a, b, beta, and c.

Local call:

When a node calls PLA_Local_syr2k, the operation is equivalent to extracting the local information (datatype, dimensions, and pointer to the buffer) and locally performing the symmetric rank-2k update. Notice that the local portion of c must be square, symmetric, and stored in the indicated portion of the buffer. The local dimensions of alpha and beta must be tex2html_wrap_inline14923 , but they can be of any object type. The local dimensions of a, b, and c must be such that the operation is well-defined. All objects must have the same datatype. Notice: no communication is performed as part of this call. Thus, all information must be locally available.

Global call:

All nodes must simultaneously call PLA_Syr2k, which performs the BLAS call on the distributed objects. Parameters uplo and trans still have the same meaning. Parameters alpha and beta must now be tex2html_wrap_inline14925 multiscalars. Parameters a, b, and c must both be of object type matrix. The global dimensions of the different objects must be such that the operation is well-defined.


next up previous contents
Next: Triangular Matrix-Matrix Multiplication Up: Symmetric Rank-2k Update Previous: PLAPACK FORTRAN-C interface

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