cpotrf.f(3)

🎀 cpotrf.f(3) — LAPACK, but make it cute 🎀

okay bestie, welcome to the cpotrf.f(3) page from the LAPACK manual 💖 this one is all about that Cholesky factorization life, and yes, we're gonna keep every single detail. periodt. ✨

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🌸 NAME 🌸

cpotrf.f — that's the name, and honestly it's iconic. 💅

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✨ SYNOPSIS ✨

Functions/Subroutines

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

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🦋 Function/Subroutine Documentation 🦋

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

CPOTRF VARIANT: right looking block version of the algorithm, calling Level 3 BLAS. no cap, that's the whole vibe. 🫶

🎯 Purpose 🎯

Okay so CPOTRF computes the Cholesky factorization of a real Hermitian positive definite matrix A. Yes, real Hermitian, that's what it says, bestie. 😭

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.

🧸 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 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.

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👑 Author 👑

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

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📅 Date 📅

December 2016

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

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✨ Author ✨

Generated automatically by Doxygen for LAPACK from the source code.

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mwah 💋 this cpotrf.f(3) page is LAPACK Version 3.8.0, dated Tue Nov 14 2017 — ty for reading, bestie 🫶