DPOT01(3)

💖 NAME 💖

okay so bestie, this is the dpot01.f(3) page from the Library Functions Manual — manual name folded in right at the top, no cap. The file is literally:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/dpot01.f

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✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

subroutine DPOT01 (uplo, n, a, lda, afac, ldafac, rwork, resid)

DPOT01 💅

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🦋 Function/Subroutine Documentation 🦋

subroutine DPOT01 (character uplo, integer n, double precision, dimension(
    lda, * ) a, integer lda, double precision, dimension( ldafac, * ) afac,
    integer ldafac, double precision, dimension( * ) rwork, double precision
    resid)

DPOT01 👑

🎀 Purpose 🎀

DPOT01 reconstructs a symmetric positive definite matrix A from its L*L' or U'*U factorization and computes the residual — literally these formulas, bestie:

norm( L*L' - A ) / ( N * norm(A) * EPS ) or
norm( U'*U - A ) / ( N * norm(A) * EPS ),

where EPS is the machine epsilon. periodt. 💅

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🌈 Parameters 🌈

💅 UPLO

UPLO is CHARACTER*1. It 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). On entry, the factor L or U from the L * L**T or U**T * U factorization of A.

Overwritten with the reconstructed matrix, and then with the difference L * L**T - A (or U**T * U - A). it's giving “I contain multitudes” energy, honestly.

👑 LDAFAC

LDAFAC is INTEGER. The leading dimension of the array AFAC. LDAFAC >= max(1,N).

🌸 RWORK

RWORK is DOUBLE PRECISION array, dimension (N).

⭐ RESID

RESID is DOUBLE PRECISION.

• If UPLO = 'L', norm(L * L**T - A) / ( N * norm(A) * EPS )
• If UPLO = 'U', norm(U**T * U - A) / ( N * norm(A) * EPS )

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👑 Author 👑

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

Definition at line 103 of file dpot01.f.

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🤖 Author (Doxygen's note) 🤖

Generated automatically by Doxygen for LAPACK from the source code.

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Footer sign-off, bestie: LAPACK Version 3.12.0, footer path /home/abui...IN/dpot01.f(3) — the date wasn't printed in this footer, so no fake date, just vibes. mwah 💋✨