The El Capitan systems provide users with the Cray LibSci collection. Most users will find they obtain better performance by using calls to Cray LibSci routines in their applications instead of calls to public domain or user-written versions. Most LibSci components provide both single-processor and parallel routines optimized specifically to make best use of Cray processors and interconnect architectures.

The general components of Cray LibSci are:

  • BLAS (Basic Linear Algebra Subroutines) 
  • CBLAS (C interface to BLAS)
  • BLACS (Basic Linear Algebra Communication Subprograms)
  • LAPACK (Linear Algebra routines)
  • ScaLAPACK (parallel Linear Algebra routines)
  • IRT (Iterative Refinement Toolkit) - a library of solvers and tools that provides solutions to linear systems using single-precision factorizations while preserving accuracy through mixed-precision iterative refinement.
  • CrayBLAS - a library of BLAS routines highly optimized for Cray systems. For further information, see intro_blas3(3s).

Additional information can be found in the Cray Scientific and Math Libraries user guide or by running the command man intro_libsci on the El Capitan systems.