/home/abui...lasyf_aa.f(3)

💅 /home/abui...lasyf_aa.f(3) — Library Functions Manual 💅

okay so bestie, this page is from the Library Functions Manual and it's all about one very specific LAPACK file. it's giving "one function, zero chill" and honestly? iconic. 🫶

🎀 NAME 🎀

The file is literally this path, character for character:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/slasyf_aa.f

✨ SYNOPSIS ✨

Functions/Subroutines 🦋

subroutine SLASYF_AA (uplo, j1, m, nb, a, lda, ipiv, h, ldh, work)
    SLASYF_AA

🌸 Function/Subroutine Documentation 🌸

Here's the full signature, bestie — every type and dimension stays exactly where it belongs:

subroutine SLASYF_AA (character uplo, integer j1, integer m, integer nb,
    real, dimension( lda, * ) a, integer lda, integer, dimension( * ) ipiv,
    real, dimension( ldh, * ) h, integer ldh, real, dimension( * ) work)
    SLASYF_AA

🍓 Purpose 🍓

okay so DLATRF_AA factorizes a panel of a real symmetric matrix A using the Aasen's algorithm. The panel consists of a set of NB rows of A when UPLO is U, or a set of NB columns when UPLO is L. 💖

In order to factorize the panel, the Aasen's algorithm requires the last row, or column, of the previous panel. The first row, or column, of A is set to be the first row, or column, of an identity matrix, which is used to factorize the first panel.

The resulting J-th row of U, or J-th column of L, is stored in the (J-1)-th row, or column, of A (without the unit diagonals), while the diagonal and subdiagonal of A are overwritten by those of T.

🌈 Parameters 🌈

• UPLO — is CHARACTER*1. = 'U': Upper triangle of A is stored; = 'L': Lower triangle of A is stored. 💅
• J1 — is INTEGER. The location of the first row, or column, of the panel within the submatrix of A, passed to this routine, e.g., when called by SSYTRF_AA, for the first panel, J1 is 1, while for the remaining panels, J1 is 2.
• M — is INTEGER. The dimension of the submatrix. M >= 0.
• NB — is INTEGER. The dimension of the panel to be facotorized. yes, that spelling is staying, no cap. 🙈
• A — is REAL array, dimension (LDA,M) for the first panel, while dimension (LDA,M+1) for the remaining panels. On entry, A contains the last row, or column, of the previous panel, and the trailing submatrix of A to be factorized, except for the first panel, only the panel is passed. On exit, the leading panel is factorized. ✨
• LDA — is INTEGER. The leading dimension of the array A. LDA >= max(1,M).
• IPIV — is INTEGER array, dimension (M). Details of the row and column interchanges, the row and column k were interchanged with the row and column IPIV(k).
• H — is REAL workspace, dimension (LDH,NB). 🦋
• LDH — is INTEGER. The leading dimension of the workspace H. LDH >= max(1,M).
• WORK — is REAL workspace, dimension (M). 🎀

👑 Author 👑

• Univ. of Tennessee
• Univ. of California Berkeley
• Univ. of Colorado Denver
• NAG Ltd.

Definition at line 142 of file slasyf_aa.f.

🌟 Author 🌟

Generated automatically by Doxygen for LAPACK from the source code.

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XOXO, source/version check bestie: LAPACK Version 3.12.0 💖. Footer path: /home/abui...lasyf_aa.f(3). mwah 💋✨