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

🦋 /home/abui...syt01_aa.f(3) 🦋

okay bestie, this is a page from the Library Functions Manual, and it's giving very specific LAPACK testing energy. no cap, every detail is staying. 💅

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🌸 NAME 🌸

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/dsyt01_aa.f

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✨ SYNOPSIS ✨

🧚 Functions/Subroutines

subroutine DSYT01_AA (uplo, n, a, lda, afac, ldafac, ipiv, c, ldc,
    rwork, resid)
    DSYT01

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💖 Function/Subroutine Documentation 💖

subroutine DSYT01_AA (character uplo, integer n, double precision,
    dimension( lda, * ) a, integer lda, double precision, dimension( ldafac,
    * ) afac, integer ldafac, integer, dimension( * ) ipiv, double
    precision, dimension( ldc, * ) c, integer ldc, double precision,
    dimension( * ) rwork, double precision resid)
    DSYT01

🎯 Purpose

okay so DSYT01 reconstructs a symmetric indefinite matrix A from its block L*D*L' or U*D*U' factorization, and then computes the residual:

norm( C - A ) / ( N * norm(A) * EPS ),

where C is the reconstructed matrix and EPS is the machine epsilon. that's the whole vibe. ✨

🧾 Parameters

• UPLO — UPLO is CHARACTER*1. specifies whether the upper or lower triangular part of the symmetric matrix A is stored:
  • = 'U': Upper triangular
  • = 'L': Lower triangular
• N — N is INTEGER. the number of rows and columns of the matrix A. N >= 0. 🫶
• A — A is DOUBLE PRECISION array, dimension (LDA,N). the original symmetric matrix A. 💖
• LDA — LDA is INTEGER. the leading dimension of the array A. LDA >= max(1,N). 👑
• AFAC — AFAC is DOUBLE PRECISION 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 DSYTRF. 🔥
• LDAFAC — LDAFAC is INTEGER. the leading dimension of the array AFAC. LDAFAC >= max(1,N). 💅
• IPIV — IPIV is INTEGER array, dimension (N). the pivot indices from DSYTRF. 🌟
• C — C is DOUBLE PRECISION array, dimension (LDC,N). literally that. ✨
• LDC — LDC is INTEGER. the leading dimension of the array C. LDC >= max(1,N). 🎀
• RWORK — RWORK is DOUBLE PRECISION array, dimension (N). yes bestie, that's the whole description. 🦋
• RESID — RESID is DOUBLE PRECISION. and the cases are:

If UPLO = 'L', norm(L*D*L' - A) / ( N * norm(A) * EPS )
If UPLO = 'U', norm(U*D*U' - A) / ( N * norm(A) * EPS )

👑 Author

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

Definition at line 122 of file dsyt01_aa.f.

🤖 Author

Generated automatically by Doxygen for LAPACK from the source code.

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okay bye bestie 💖 this is LAPACK, Version 3.12.0, /home/abui...syt01_aa.f(3). mwah 💋✨