SRC/zpttrf.f(3)

🌸 NAME 🌸

okay so this is the LAPACK Library Functions Manual page for SRC/zpttrf.f(3), and bestie, we're talking about ZPTTRF today 💅

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✨ SYNOPSIS ✨

🫶 Functions/Subroutines 🫶

• subroutine zpttrf (n, d, e, info) — ZPTTRF

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💖 Function/Subroutine Documentation 💖

subroutine zpttrf (integer n, double precision, dimension( * ) d,
    complex*16, dimension( * ) e, integer info)
    ZPTTRF

🎀 Purpose 🎀

ZPTTRF computes the L*D*L**H factorization of a complex Hermitian positive definite tridiagonal matrix A. The factorization may also be regarded as having the form A = U**H *D*U. no cap, that's the whole glow-up ✨

🌈 Parameters 🌈

• N — N is INTEGER, and it's the order of the matrix A. N >= 0. periodt 💜
• D — D is a DOUBLE PRECISION array, dimension (N). On entry, it holds the n diagonal elements of the tridiagonal matrix A. On exit, it holds the n diagonal elements of the diagonal matrix D from the L*D*L**H factorization of A. she gets rewritten, iykyk 🦋
• E — E is a COMPLEX*16 array, dimension (N-1). On entry, it holds the (n-1) subdiagonal elements of the tridiagonal matrix A. On exit, it holds the (n-1) subdiagonal elements of the unit bidiagonal factor L from the L*D*L**H factorization of A. E can also be regarded as the superdiagonal of the unit bidiagonal factor U from the U**H *D*U factorization of A. multi-purpose icon behavior 🌟
• INFO — INFO is INTEGER, and it's giving status check:
  • = 0: successful exit 🎉
  • < 0: if INFO = -k, the k-th argument had an illegal value 😭
  • > 0: if INFO = k, the leading principal minor of order k is not positive; if k < N, the factorization could not be completed, while if k = N, the factorization was completed, but D(N) <= 0. bestie, read that carefully 💀

👑 Author 👑

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 91 of file zpttrf.f.

🧚 Author 🧚

Generated automatically by Doxygen for LAPACK from the source code.

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catch u later, bestie 🫶 this page is rockin' LAPACK Version 3.12.0 and the file is SRC/zpttrf.f(3) — iconic, fr fr 💅✨