potf2(3)

📦
version 3.12.1 · 9 versions
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🌸 NAME 🌸

potf2(3) — from the Library Functions Manual — is literally potf2 - potf2: triangular factor panel, level 2. That's the whole name, bestie. 💅

✨ SYNOPSIS ✨

Functions

  • subroutine cpotf2 (uplo, n, a, lda, info) — CPOTF2 computes the Cholesky factorization of a symmetric/Hermitian positive definite matrix (unblocked algorithm).
  • subroutine dpotf2 (uplo, n, a, lda, info) — DPOTF2 computes the Cholesky factorization of a symmetric/Hermitian positive definite matrix (unblocked algorithm).
  • subroutine spotf2 (uplo, n, a, lda, info) — SPOTF2 computes the Cholesky factorization of a symmetric/Hermitian positive definite matrix (unblocked algorithm).
  • subroutine zpotf2 (uplo, n, a, lda, info) — ZPOTF2 computes the Cholesky factorization of a symmetric/Hermitian positive definite matrix (unblocked algorithm).

💫 Detailed Description 💫

Okay so the original's Detailed Description section is literally empty — no tea there, bestie. The actual lore lives under Function Documentation. 🫶

🔥 Function Documentation 🔥

💖 CPOTF2 💖

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

CPOTF2 computes the Cholesky factorization of a complex Hermitian positive definite matrix A.

🎀 Purpose 🎀

CPOTF2 computes the Cholesky factorization of a complex 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 unblocked version of the algorithm, calling Level 2 BLAS. ✨

🧚 Parameters 🧚

  • UPLO — UPLO is CHARACTER*1. 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, 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.

💖 DPOTF2 💖

subroutine dpotf2 (character uplo, integer n, double precision, dimension(
       lda, * ) a, integer lda, integer info)

DPOTF2 computes the Cholesky factorization of a real symmetric positive definite matrix A.

🎀 Purpose 🎀

DPOTF2 computes the Cholesky factorization of a real symmetric positive definite matrix A.

The factorization has the form

A = U**T * U ,  if UPLO = 'U', or
A = L  * L**T,  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. ✨

🧚 Parameters 🧚

  • UPLO — UPLO is CHARACTER*1. Specifies whether the upper or lower triangular part of the symmetric 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 DOUBLE PRECISION 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**T *U or A = L*L**T.

  • 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 dpotf2.f.

💖 SPOTF2 💖

subroutine spotf2 (character uplo, integer n, real, dimension( lda, * ) a,
       integer lda, integer info)

SPOTF2 computes the Cholesky factorization of a real symmetric positive definite matrix A.

🎀 Purpose 🎀

SPOTF2 computes the Cholesky factorization of a real symmetric positive definite matrix A.

The factorization has the form

A = U**T * U ,  if UPLO = 'U', or
A = L  * L**T,  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. ✨

🧚 Parameters 🧚

  • UPLO — UPLO is CHARACTER*1. Specifies whether the upper or lower triangular part of the symmetric 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 REAL 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**T *U or A = L*L**T.

  • 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 spotf2.f.

💖 ZPOTF2 💖

subroutine zpotf2 (character uplo, integer n, complex*16, dimension( lda, *
       ) a, integer lda, integer info)

ZPOTF2 computes the Cholesky factorization of a complex Hermitian positive definite matrix A.

🎀 Purpose 🎀

ZPOTF2 computes the Cholesky factorization of a complex 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 unblocked version of the algorithm, calling Level 2 BLAS. ✨

🧚 Parameters 🧚

  • UPLO — UPLO is CHARACTER*1. 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*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 = -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 zpotf2.f.

🌸 AUTHOR 🌸

ok so real talk bestie, there's no mysterious human genius to thank for this one 💅 this entire page was generated automatically by Doxygen for LAPACK, pulled straight from the source code. like… the source code is the main character here, and the docs are just its glamorous little reflection ✨

so if something reads a lil robotic, that's because a tool wrote it, not a person 🫶 no cap, the author field is literally a doc generator doing its job.

ngl this is the part where most manpages thank a real human by name, but this one's giving "the algorithm did my homework" energy 💀 — automatic generation, for LAPACK, from the source code. periodt.

and that's a wrap on the whole vibe check, bestie 💖 you actually made it to the end of potf2(3) — iconic behavior 👑 this page comes to you from LAPACK, Version 3.12.0, generated automatically by Doxygen from the source code so you never have to go digging through the raw files yourself 🌈✨ now go forth and slay whatever you opened this page for 🦋💜

📦 where this page comes from