/home/abui...syt01_aa.f(3)

💅 NAME 💅

ok so bestie, this page is literally about a file called /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/zsyt01_aa.f — yes that's the whole entire name, she's got a long government name and she's rocking it. It's from the LAPACK library functions manual, section 3. Slay.

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✨ SYNOPSIS ✨

Functions/Subroutines 🎀

subroutine ZSYT01_AA (uplo, n, a, lda, afac, ldafac, ipiv, c, ldc,
    rwork, resid)
    ZSYT01

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🦋 Function/Subroutine Documentation 🦋

the whole signature, no cap ⭐

subroutine ZSYT01_AA (character uplo, integer n, complex*16, dimension( lda,
    * ) a, integer lda, complex*16, dimension( ldafac, * ) afac, integer
    ldafac, integer, dimension( * ) ipiv, complex*16, dimension( ldc, * ) c,
    integer ldc, double precision, dimension( * ) rwork, double precision
    resid)
ZSYT01

👑 Purpose 👑

so here's the vibe, quoted from the source !> block:

!>
!> ZSYT01 reconstructs a hermitian indefinite matrix A from its
!> block L*D*L' or U*D*U' factorization and computes the residual
!>    norm( C - A ) / ( N * norm(A) * EPS ),
!> where C is the reconstructed matrix and EPS is the machine epsilon.
!>

like, she takes A apart, rebuilds it from the blocks, and then checks how close she got. iconic behavior ngl 💖

🌸 Parameters 🌸

• UPLO — UPLO is CHARACTER*1 — tells you which triangle of the hermitian matrix A is actually stored: = 'U': Upper triangular or = 'L': Lower triangular. pick a side bestie, you can't have both 🙈
• N — N is INTEGER — the number of rows and columns of the matrix A, and N >= 0. square queen energy ⭐
• A — A is COMPLEX*16 array, dimension (LDA,N) — the original hermitian matrix A. the real one, before all the factoring drama.
• LDA — LDA is INTEGER — the leading dimension of the array A, and LDA >= max(1,N). respect the leading dimension or she will not run 💀
• AFAC — AFAC is COMPLEX*16 array, dimension (LDAFAC,N) — the factored form of the matrix A. AFAC contains the block diagonal matrix D and the multipliers used to obtain the factor L or U from the block L*D*L' or U*D*U' factorization, as computed by ZSYTRF. so like, ZSYTRF did the work and AFAC is holding the receipts 🧾
• LDAFAC — LDAFAC is INTEGER — the leading dimension of the array AFAC, and LDAFAC >= max(1,N). yes she has her own leading dimension, don't ask questions 🫶
• IPIV — IPIV is INTEGER array, dimension (N) — the pivot indices from ZSYTRF. the pivot girlies 💅
• C — C is COMPLEX*16 array, dimension (LDC,N) — ok that's literally it, that's the whole description, no further notes, we love a low-maintenance array ✨
• LDC — LDC is INTEGER — the leading dimension of the array C, and LDC >= max(1,N). third leading dimension, third time's the charm 🎀
• RWORK — RWORK is COMPLEX*16 array, dimension (N) — again, that's the whole note, she said what she said 🌈
• RESID — RESID is COMPLEX*16 — the actual residual number, and:
  • if UPLO = 'L', then norm(L*D*L' - A) / ( N * norm(A) * EPS )
  • if UPLO = 'U', then norm(U*D*U' - A) / ( N * norm(A) * EPS )

she's the final boss score at the end of the whole test 🔥

🧚 Author 🧚

the brains behind this, respectfully:

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

🍓 Where she lives 🍓

Definition at line 122 of file zsyt01_aa.f.

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💜 Author (the meta one) 💜

Generated automatically by Doxygen for LAPACK from the source code. — so nobody hand-wrote this page, a robot did, and honestly the robot ate 🤖✨

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ok that's the whole page bestie, you're welcome, go reconstruct a hermitian indefinite matrix responsibly 💖

sign-off: this was LAPACK, Version 3.12.0, and the footer path was /home/abui...syt01_aa.f(3) — mwah, periodt 🫶💅