CPOT01(3)

💖 CPOT01 💖

okay bestie, so this page is all about cpot01.f — yes, it literally lives at /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/cpot01.f, that's the whole NAME situation, we don't gatekeep file paths here 💅 — and it's one of those LAPACK testing-helper girlies that checks whether a factorization actually slayed.

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✨ SYNOPSIS ✨

🎀 Functions/Subroutines

• subroutine CPOT01 (uplo, n, a, lda, afac, ldafac, rwork, resid) — and that's it, that's the whole function. CPOT01. icon behavior honestly.

🦋 Function/Subroutine Documentation 🦋

subroutine CPOT01 (character uplo, integer n, complex, dimension( lda, * )
    a, integer lda, complex, dimension( ldafac, * ) afac, integer ldafac,
    real, dimension( * ) rwork, real resid)

CPOT01 (again, yes, that's the name, we said it)

🌸 Purpose 🌸

so here's the vibe, fr:

!>
!> CPOT01 reconstructs a Hermitian positive definite matrix  A  from
!> its L*L' or U'*U factorization and computes the residual
!>    norm( L*L' - A ) / ( N * norm(A) * EPS ) or
!>    norm( U'*U - A ) / ( N * norm(A) * EPS ),
!> where EPS is the machine epsilon, L' is the conjugate transpose of L,
!> and U' is the conjugate transpose of U.
!>

like, it takes your Hermitian positive definite matrix A, rebuilds it from the L*L' or U'*U factorization, and then does a little vibe check to see how far off the reconstruction is from the original. main character energy 🔥

💜 Parameters 💜

• UPLO — UPLO is CHARACTER*1. it tells you 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). On entry, the factor L or U from the L * L**H or U**H * U factorization of A. ⚠️ it gets Overwritten with the reconstructed matrix, and then with the difference L * L**H - A (or U**H * U - A). so like, your input is NOT surviving this, periodt 💀
• LDAFAC — LDAFAC is INTEGER. The leading dimension of the array AFAC. LDAFAC >= max(1,N).
• RWORK — RWORK is REAL array, dimension (N)
• RESID — RESID is REAL.
  • If UPLO = 'L', norm(L * L**H - A) / ( N * norm(A) * EPS )
  • If UPLO = 'U', norm(U**H * U - A) / ( N * norm(A) * EPS )

👑 Author 👑

the credits, bestie, we respect the legends:

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

Definition at line 105 of file cpot01.f.

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🌈 Author (the meta one) 🌈

Generated automatically by Doxygen for LAPACK from the source code. not a human, not a vibe, just a doc generator doing its thing 🫶

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and that's the whole page, bestie!! ✨ this was LAPACK Version 3.12.0, dated /home/abui...IN/cpot01.f(3) — well, that's the file path it stamped on the footer, we're just reporting the facts 💖 go forth and reconstruct your Hermitian positive definite matrices, ily, bye 🎀