TESTING/LIN/csyt01.f(3)

okay so welcome to the TESTING/LIN/csyt01.f(3) manual page, bestie 💖 — this whole page is about the csyt01 subroutine, and we are gonna get through every single detail together. Periodt.

🌸 NAME 🌸

TESTING/LIN/csyt01.f — that's the name on the door, and this page is all about the csyt01 subroutine. 🫶

✨ SYNOPSIS ✨

🦋 Functions/Subroutines 🦋

subroutine csyt01 (uplo, n, a, lda, afac, ldafac, ipiv, c, ldc, rwork,
           resid)

CSYT01

💅 Function/Subroutine Documentation 💅

subroutine csyt01 (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)

CSYT01

🎀 Purpose 🎀

CSYT01 reconstructs a complex 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, EPS is the machine epsilon, L' is the transpose of L, and U' is the transpose of U. 🦋

🌸 Parameters 🌸

• UPLO — UPLO is CHARACTER*1. It says whether the upper or lower triangular part of the complex 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 COMPLEX array, dimension (LDA,N). The original complex symmetric 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 CSYTRF.
• 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 CSYTRF.
• 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 REAL array, dimension (N).
• RESID — RESID is REAL. 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 ).

👑 Author 👑

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

Definition at line 123 of file csyt01.f.

🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code.

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