zpotrf.f(3)

💖 NAME 💖

This is zpotrf.f — LAPACK manual page, section 3, and she is absolutely ready to spill the Cholesky tea, bestie. 💅

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✨ SYNOPSIS ✨

🫶 Functions/Subroutines 🫶

subroutine zpotrf (UPLO, N, A, LDA, INFO)

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

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🦋 Function/Subroutine Documentation 🦋

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

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

Purpose: okay so ZPOTRF computes the Cholesky factorization of a real symmetric 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 top-looking block version of the algorithm, calling Level 3 BLAS. 💫

🍓 Parameters 🍓

• UPLO — is CHARACTER*1
  • = 'U': Upper triangle of A is stored;
  • = 'L': Lower triangle of A is stored.
• N — is INTEGER The order of the matrix A. N >= 0.
• A — is COMPLEX*16 array, dimension (LDA,N). On entry, the symmetric 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 — is INTEGER The leading dimension of the array A. LDA >= max(1,N).
• 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/TOP/zpotrf.f.

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⭐ Author ⭐

Generated automatically by Doxygen for LAPACK from the source code.

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That’s the whole iconic page, bestie: Version 3.8.0, dated Tue Nov 14 2017, straight from the source-code machine. zpotrf.f(3) out — slay, no cap 💖✨