Developer Reference

  • 2021.1
  • 12/04/2020
  • Public Content

BLACS Routines

Intel® oneAPI
Math Kernel Library
FORTRAN 77 routines from the BLACS (Basic Linear Algebra Communication Subprograms) package. These routines are used to support a linear algebra oriented message passing interface that may be implemented efficiently and uniformly across a large range of distributed memory platforms.
The BLACS routines make linear algebra applications both easier to program and more portable. For this purpose, they are used in
Intel® oneAPI Math Kernel Library
intended for the Linux* and Windows* OSs as the communication layer of ScaLAPACK and Cluster FFT.
On computers, a linear algebra matrix is represented by a two dimensional array (2D array), and therefore the BLACS operate on 2D arrays. See description of the basic matrix shapes in a special
The BLACS routines implemented in
Intel® oneAPI Math Kernel Library
are of four categories:
  • Combines
  • Point to Point Communication
  • Broadcast
  • Support.
The Combines take data distributed over processes and combine the data to produce a result. The Point to Point routines are intended for point-to-point communication and Broadcast routines send data possessed by one process to all processes within a scope.
The Support routines perform distinct tasks that can be used for initialization, destruction, information, and miscellaneous tasks.
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Notice revision #20110804
This notice covers the following instruction sets: SSE2, SSE4.2, AVX2, AVX-512.

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