SRC/cpotf2.f(3)

💖 SRC/cpotf2.f(3) 💖

hii bestie, welcome to the Library Functions Manual! this page is for SRC/cpotf2.f, and it's fully about CPOTF2 — the unblocked Cholesky factorization subroutine. okay so let's get into it, no cap. 🫶

🌸 NAME 🌸

SRC/cpotf2.f

✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine cpotf2 (uplo, n, a, lda, info) — CPOTF2 computes the Cholesky factorization of a symmetric/Hermitian positive definite matrix (unblocked algorithm).

💅 Function/Subroutine Documentation 💅

subroutine cpotf2 (character uplo, integer n, complex, dimension( lda, * ) a, integer lda, integer info)

CPOTF2 computes the Cholesky factorization of a symmetric/Hermitian positive definite matrix (unblocked algorithm).

🎀 Purpose 🎀

okay so CPOTF2 computes the Cholesky factorization of a complex Hermitian positive definite matrix A. it's giving iconic linear algebra behavior, fr fr.

the factorization has the form

A = U**H * U ,  if UPLO = 'U', or
A = L  * L**H,  if UPLO = 'L',

where U is an upper triangular matrix and L is lower triangular.

this is the unblocked version of the algorithm, calling Level 2 BLAS. periodt.

🌈 Parameters 🌈

🦋 UPLO

UPLO is CHARACTER*1. it specifies 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 order of the matrix A. N >= 0.

🍓 A

A is COMPLEX array, dimension (LDA,N). on entry, it's the Hermitian matrix A. if UPLO = 'U', the leading n by n upper triangular part of A contains the upper triangular part of the matrix A, and the strictly lower triangular part of A is not referenced. if UPLO = 'L', the leading n by n lower triangular part of A contains the lower triangular part of the matrix A, and the strictly upper triangular part of A is not referenced.

on exit, if INFO = 0, the factor U or L from the Cholesky factorization A = U**H *U or A = L*L**H.

🧚 LDA

LDA is INTEGER. the leading dimension of the array A. LDA >= max(1,N).

💜 INFO

INFO is INTEGER.

• = 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, and the factorization could not be completed.

👑 Author

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

📍 Definition at line 108 of file cpotf2.f.

📝 Author 📝

Generated automatically by Doxygen for LAPACK from the source code.

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xoxo bestie — this page is from LAPACK Version 3.12.0, and its manual-page path is SRC/cpotf2.f(3). slay responsibly. 💅✨