TESTING/LIN/chet01_aa.f(3)

💖 TESTING/LIN/chet01_aa.f(3) 💖

Library Functions Manual — that’s the manual name, bestie, folded in right here near the top so we don’t do a whole duplicate header line. ✨

✨ NAME ✨

TESTING/LIN/chet01_aa.f — that’s the name. Periodt. 🎀

🎀 SYNOPSIS 🎀

Functions/Subroutines — the lineup:

       subroutine chet01_aa (uplo, n, a, lda, afac, ldafac, ipiv, c, ldc,
           rwork, resid)
           CHET01_AA

💅 Function/Subroutine Documentation 💅

Okay so here’s the full signature, exactly as it appears, no cap:

   subroutine chet01_aa (character uplo, integer n, complex, dimension( lda, *
       ) a, integer lda, complex, dimension( ldafac, * ) afac, integer ldafac,
       integer, dimension( * ) ipiv, complex, dimension( ldc, * ) c, integer
       ldc, real, dimension( * ) rwork, real resid)
       CHET01_AA

CHET01_AA — iconic. 🫶

🧚 Purpose

CHET01_AA 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. 💅

🌸 Parameters 🌸

• UPLO — UPLO is CHARACTER*1; it specifies whether the upper or lower triangular part of the hermitian 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 COMPLEX array, dimension (LDA,N); the original hermitian matrix A.
• LDA — LDA is INTEGER; the leading dimension of the array A. LDA >= max(1,N).
• AFAC — AFAC is COMPLEX 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 CHETRF.
• 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 CHETRF.
• C — C is COMPLEX array, dimension (LDC,N).
• LDC — LDC is INTEGER; the leading dimension of the array C. LDC >= max(1,N).
• RWORK — RWORK is COMPLEX array, dimension (N). (Yes bestie, the original says COMPLEX here — no edits. 🫶)
• RESID — RESID is COMPLEX; 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 chet01_aa.f.

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

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That’s the whole page, bestie 💖 — footer source/version is LAPACK Version 3.12.0, and the page tag is TESTING/LIN/chet01_aa.f(3). Slay. 🌈