DSYT01(3)

🎀 DSYT01(3) 🎀

okay so bestie, we’re in the Library Functions Manual and this page is the whole DSYT01(3) situation. It’s giving LAPACK testing energy, and the NAME section is literally a path — yes, a whole path as the name, iconic chaos:

💖 NAME 💖

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/dsyt01.f

That path is exact, no editing it.

✨ SYNOPSIS ✨

Functions/Subroutines

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

DSYT01 — that’s the subroutine, periodt.

🧚 Function/Subroutine Documentation 🧚

subroutine DSYT01 (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 again, slay.

💫 Purpose 💫

okay so DSYT01 reconstructs a symmetric 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. No cap, that’s the whole purpose 💅.

🦋 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)

⭐ LDC

• LDC is INTEGER
• The leading dimension of the array C. LDC >= max(1,N).

🧚 RWORK

• RWORK is DOUBLE PRECISION array, dimension (N)

👑 RESID

• RESID is DOUBLE PRECISION
• 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.f.

🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code.

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okay bye bestie 🫶 — the footer vibe was LAPACK Version 3.12.0 with /home/abui...IN/dsyt01.f(3), and yeah there wasn’t an actual date in the footer, just those. 💖✨