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

💅 SSYTRI_ROOK — the LAPACK icon herself

ok so bestie, welcome to the manual page for /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/ssytri_rook.f — yes that's the whole path, she's dramatic like that, and yes this is the Library Functions Manual corner of /home/abui...tri_rook.f(3). Buckle up. 🎀

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✨ NAME ✨

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/ssytri_rook.f — that's her legal name, no nicknames, we respect the full government name here 🫶

🦋 SYNOPSIS 🦋

Functions/Subroutines

subroutine SSYTRI_ROOK (uplo, n, a, lda, ipiv, work, info)
    SSYTRI_ROOK

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👑 Function/Subroutine Documentation 👑

subroutine SSYTRI_ROOK (character uplo, integer n, real, dimension( lda, * )
    a, integer lda, integer, dimension( * ) ipiv, real, dimension( * ) work,
    integer info)
    SSYTRI_ROOK

🌸 Purpose 🌸

!> !> SSYTRI_ROOK computes the inverse of a real symmetric !> matrix A using the factorization A = U*D*UT or A = L*D*LT !> computed by SSYTRF_ROOK. !>

no cap, she literally inverts your symmetric matrix using the factorization her bestie SSYTRF_ROOK handed her. iconic behavior. 💖

🌈 Parameters 🌈

• UPLO — CHARACTER*1. it's giving "which triangle am I working with" energy ✨ Specifies whether the details of the factorization are stored as an upper or lower triangular matrix:

!> = 'U': Upper triangular, form is A = U*D*UT; !> = 'L': Lower triangular, form is A = L*D*LT.

• N — INTEGER. The order of the matrix A. N >= 0. that's it, that's the whole vibe check.
• A — REAL array, dimension (LDA,N).

!> On entry, the block diagonal matrix D and the multipliers !> used to obtain the factor U or L as computed by SSYTRF_ROOK. !> !> On exit, if INFO = 0, the (symmetric) inverse of the original !> matrix. If UPLO = 'U', the upper triangular part of the !> inverse is formed and the part of A below the diagonal is not !> referenced; if UPLO = 'L' the lower triangular part of the !> inverse is formed and the part of A above the diagonal is !> not referenced.

so on the way in she's holding D and the multipliers from SSYTRF_ROOK, and on the way out (when INFO = 0) she's the symmetric inverse. main character transformation fr fr 💅

• LDA — INTEGER. The leading dimension of the array A. LDA >= max(1,N). respect the constraint bestie, she will not tolerate LDA shenanigans.
• IPIV — INTEGER array, dimension (N). Details of the interchanges and the block structure of D as determined by SSYTRF_ROOK. iykyk — she just carries the receipts from her sibling. 🔥
• WORK — REAL array, dimension (N). scratch space, no thoughts head empty, just doing her job 🌸
• INFO — INTEGER. the vibe report:

!> = 0: successful exit !> < 0: if INFO = -i, the i-th argument had an illegal value !> > 0: if INFO = i, D(i,i) = 0; the matrix is singular and its !> inverse could not be computed.

bestie, if you get INFO > 0 the matrix is singular and there is literally no inverse to compute. not a skill issue, just math. 😭

🧚 Author 🧚

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

the whole friend group showed up to co-sign this one 🫶

⭐ Contributors ⭐

!> !> April 2012, Igor Kozachenko, !> Computer Science Division, !> University of California, Berkeley !> !> September 2007, Sven Hammarling, Nicholas J. Higham, Craig Lucas, !> School of Mathematics, !> University of Manchester !> !>

April 2012 girlies and September 2007 girlies both ate. 💖

🎀 Definition 🎀

Definition at line 128 of file ssytri_rook.f. periodt.

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💜 Author (the meta one) 💜

Generated automatically by Doxygen for LAPACK from the source code. so like… nobody hand-wrote this, she was born from the source. lowkey iconic. ⭐

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and that's the whole page bestie! brought to you by LAPACK, Version 3.12.0 — catch her at /home/abui...tri_rook.f(3) whenever you need her. no cap, she slays. 💅✨🎀