cray-libsci Overview

Cray LibSci is a collection of numerical routines tuned for performance on Cray XT, Cray XE, and Cray XK systems. Most users, on most codes, 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. Note: Additionally, Cray XK systems also make use of the Cray LibSci Accelerator routines, for enhanced performance on GPU-equipped Cray XK compute nodes. For more information, see the intro_libsci_acc man page. Most LibSci components contain 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)
  • BLACS (Basic Linear Algebra Communication Subprograms)
  • LAPACK (Linear Algebra routines)
  • ScaLAPACK (parallel Linear Algebra routines)
  • FFT (Fast Fourier Transforms)
  • FFTW (Fastest FFT in the West)
Three libraries unique to Cray are:
  • CRAFFT (Cray Adaptive FFT routines) - a library of serial and parallel, single- and double-precision, Fortran and C routines that compute the discrete Fourier transform in one, two, or three dimensions. CRAFFT provides a simplified interface to several FFT libraries and allows automatic, dynamic selection of the fastest FFT kernel.
  • CASE (Cray Adaptive Simple Eigensolver) - a collection of simplified interfaces into high-performance LAPACK and ScaLAPACK eigensolver routines that construct the sometimes complicated LAPACK and ScaLAPACK eigensolver calling sequences and work arrays from simple arguments.
  • 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.


For more information see the libsci man page and view the module help:
module load cray-libsci
module help cray-libsci
man intro_libsci
The libsci routeine man pages have further information:
  • intro_libsci_acc
  • intro_crafft
  • intro_case
  • intro_irt
  • intro_blacs
  • intro_blas1
  • intro_blas2
  • intro_blas3
  • intro_fft
  • intro_fftw2
  • intro_fftw3
  • intro_lapack
  • intro_scalapack


  • 13.2.0
  • 13.3.0
  • 16.03.1
  • 16.06.1
  • 16.11.1


  • 13.0.4
  • 13.2.0
  • 13.3.0
  • 16.03.1
  • 16.06.1
  • 16.09.1
  • 16.11.1
  • 17.06.1
  • 17.09.1