SRC/ssb2st_kernels.f(3)

✨ SRC/ssb2st_kernels.f ✨

okay so this is a page from the LAPACK manual (that's the library name, bestie, it's giving "Library Functions Manual" energy) and it's all about one very specific little internal workhorse routine πŸ’…


🌸 SYNOPSIS 🌸

Functions/Subroutines

  • subroutine ssb2st_kernels (uplo, wantz, ttype, st, ed, sweep, n, nb, ib, a, lda, v, tau, ldvt, work) β€” literally the whole point of this page, it's SSB2ST_KERNELS πŸŽ€

πŸ‘‘ Function/Subroutine Documentation πŸ‘‘

subroutine ssb2st_kernels (character uplo, logical wantz, integer ttype,
    integer st, integer ed, integer sweep, integer n, integer nb, integer
    ib, real, dimension( lda, * ) a, integer lda, real, dimension( * ) v,
    real, dimension( * ) tau, integer ldvt, real, dimension( * ) work)

πŸ’– SSB2ST_KERNELS πŸ’–

Purpose:

so the deal is β€” SSB2ST_KERNELS is an internal routine used by the SSYTRD_SB2ST subroutine. that's it, that's the whole purpose. it's a backstage-pass kind of routine, not the main character (but like, every main character needs a support system, periodt) πŸ¦‹

Parameters

  • UPLO β€” UPLO is CHARACTER*1 ⭐ (that's all it says, no cap, the docs are leaving it mysterious)
  • WANTZ β€” WANTZ is LOGICAL which indicate if Eigenvalue are requested or both Eigenvalue/Eigenvectors πŸ’« so like, are we just getting the numbers or the numbers and the vectors
  • TTYPE β€” TTYPE is INTEGER 🌈
  • ST β€” ST is INTEGER. internal parameter for indices πŸ”₯
  • ED β€” ED is INTEGER. internal parameter for indices πŸ”₯
  • SWEEP β€” SWEEP is INTEGER. internal parameter for indices πŸ”₯
  • N β€” N is INTEGER. The order of the matrix A. πŸ’œ
  • NB β€” NB is INTEGER. The size of the band. πŸŽ€
  • IB β€” IB is INTEGER. 🫢
  • A β€” A is REAL array. A pointer to the matrix A. 🌸
  • LDA β€” LDA is INTEGER. The leading dimension of the matrix A. ✨
  • V β€” V is REAL array, dimension 2*n if eigenvalues only are requested or to be queried for vectors. πŸ¦‹
  • TAU β€” TAU is REAL array, dimension (2*n). The scalar factors of the Householder reflectors are stored in this array. πŸ’…
  • LDVT β€” LDVT is INTEGER. ⭐
  • WORK β€” WORK is REAL array. Workspace of size nb. 🧚

Further Details:

  • Implemented by Azzam Haidar. πŸ‘‘
  • All details are available on technical report, SC11, SC13 papers. πŸ“š
  • Azzam Haidar, Hatem Ltaief, and Jack Dongarra. Parallel reduction to condensed forms for symmetric eigenvalue problems using aggregated fine-grained and memory-aware kernels. In Proceedings of 2011 International Conference for High Performance Computing, Networking, Storage and Analysis (SC '11), New York, NY, USA, Article 8, 11 pages. http://doi.acm.org/10.1145/2063384.2063394 πŸ”₯
  • A. Haidar, J. Kurzak, P. Luszczek, 2013. An improved parallel singular value algorithm and its implementation for multicore hardware, In Proceedings of 2013 International Conference for High Performance Computing, Networking, Storage and Analysis (SC '13). Denver, Colorado, USA, 2013. Article 90, 12 pages. http://doi.acm.org/10.1145/2503210.2503292 πŸ”₯
  • A. Haidar, R. Solca, S. Tomov, T. Schulthess and J. Dongarra. A novel hybrid CPU-GPU generalized eigensolver for electronic structure calculations based on fine-grained memory aware tasks. International Journal of High Performance Computing Applications. Volume 28 Issue 2, Pages 196-209, May 2014. http://hpc.sagepub.com/content/28/2/196 πŸ”₯
ngl the citation section is lowkey the most extra part of this whole page and honestly? respect. three whole papers. she did her homework πŸ’€πŸ’–

πŸ“ Definition at line 170 of file ssb2st_kernels.f. πŸ“


🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code. (yes bestie, a robot wrote this, don't come for me πŸ™ˆ)


and that's the whole vibe check! this page is from LAPACK, Version 3.12.0, and it's literally SRC/ssb2st_kernels.f(3) β€” like, that's the file, that's the section, we're done here. slay, go read the actual source if you need more πŸ“πŸ’œ

πŸ“¦ where this page comes from