DPST01(3)

💅 DPST01(3) — Library Functions Manual 💅

okay so bestie, welcome to DPST01(3), straight out of the Library Functions Manual. This is the page for the DPST01 subroutine, and it is lowkey giving main character energy. 💖

✨ NAME ✨

• /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/dpst01.f — yep, that is the whole name/path, and I am not editing one character of it. periodt. 🎀

🦋 SYNOPSIS 🦋

Functions/Subroutines

subroutine DPST01 (uplo, n, a, lda, afac, ldafac, perm, ldperm, piv,
    rwork, resid, rank)

• DPST01 — the subroutine itself, iconic behavior only. 👑

👑 Function/Subroutine Documentation 👑

subroutine DPST01 (character uplo, integer n, double precision, dimension(
    lda, * ) a, integer lda, double precision, dimension( ldafac, * ) afac,
    integer ldafac, double precision, dimension( ldperm, * ) perm, integer
    ldperm, integer, dimension( * ) piv, double precision, dimension( * )
    rwork, double precision resid, integer rank)

DPST01

Purpose

DPST01 reconstructs a symmetric positive semidefinite matrix A from its L or U factors and the permutation matrix P, and then computes the residual:

norm( P*L*L'*P' - A ) / ( N * norm(A) * EPS )

or

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

where EPS is the machine epsilon. ngl, that is 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 factor L or U from the L*L' or U'*U factorization of A.
• LDAFAC — LDAFAC is INTEGER. The leading dimension of the array AFAC. LDAFAC >= max(1,N).
• PERM — PERM is DOUBLE PRECISION array, dimension (LDPERM,N). Overwritten with the reconstructed matrix, and then with the difference P*L*L'*P' - A (or P*U'*U*P' - A)
• LDPERM — LDPERM is INTEGER. The leading dimension of the array PERM. LDAPERM >= max(1,N). yes bestie, the source says LDAPERM right there, and I am keeping it exactly like that. 💅
• PIV — PIV is INTEGER array, dimension (N). PIV is such that the nonzero entries are P( PIV( K ), K ) = 1.
• RWORK — RWORK is DOUBLE PRECISION array, dimension (N)
• RESID — RESID is DOUBLE PRECISION. If UPLO = 'L', norm(L*L' - A) / ( N * norm(A) * EPS ). If UPLO = 'U', norm(U'*U - A) / ( N * norm(A) * EPS ).
• RANK — RANK is INTEGER. number of nonzero singular values of A.

🌸 Author 🌸

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

Definition at line 132 of file dpst01.f.

🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code.

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okay that is the whole thing, bestie. This cutie is from LAPACK Version 3.12.0, and the footer path is /home/abui...IN/dpst01.f(3). slay, you made it to the end. 💖✨🎀