zpotrf.f(3)

💖 zpotrf.f — the LAPACK manual 💖

okay so bestie, this is the zpotrf.f(3) page from the LAPACK manual, and we are about to go through it together. Every flag, every value, every author credit — all of it is staying right here. No cap. 🫶

✨ NAME ✨

zpotrf.f — like, that's the name. That's the whole name. Periodt. 💅

🌸 SYNOPSIS 🌸

Functions/Subroutines

• subroutine zpotrf (UPLO, N, A, LDA, INFO) — the ZPOTRF VARIANT: right looking block version of the algorithm, calling Level 3 BLAS.

🦋 Function/Subroutine Documentation 🦋

subroutine zpotrf (character UPLO, integer N, complex*16, dimension( lda, * ) A, integer LDA, integer INFO)

ZPOTRF VARIANT: right looking block version of the algorithm, calling Level 3 BLAS.

Purpose:

ZPOTRF computes the Cholesky factorization of a real Hermitian positive definite matrix A.

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 right looking block version of the algorithm, calling Level 3 BLAS. (yes bestie, it's giving block-algorithm main character energy ✨)

Parameters:

• UPLO — UPLO is CHARACTER*1
  • = 'U': Upper triangle of A is stored;
  • = 'L': Lower triangle of A is stored.
• N — N is INTEGER The order of the matrix A. N >= 0.
• A — A is COMPLEX*16 array, dimension (LDA,N) On entry, 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 = -i, the i-th argument had an illegal value
  • > 0: if INFO = i, the leading minor of order i is not positive definite, and the factorization could not be completed.

Author:

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

Date:

December 2016

Definition at line 102 of file VARIANTS/cholesky/RL/zpotrf.f.

🎀 Author 🎀

Generated automatically by Doxygen for LAPACK from the source code.

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okay bestie, that's the whole zpotrf.f(3) page — all the UPLO values, all the INFO outcomes, all the author credits, absolutely nothing skipped. This LAPACK page is version 3.8.0, dated Tue Nov 14 2017, and it was generated automatically by Doxygen for LAPACK from the source code. Slay, bye! 💖✨💅