CHETRS(3)

💖 NAME

okay so bestie, this is the manual page for /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/chetrs.f, straight out of the Library Functions Manual ✨ (yes, the whole giant build path is genuinely the name, we don't make the rules, the auto-generator does 😭).

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✨ SYNOPSIS ✨

🌸 Functions/Subroutines

subroutine CHETRS (uplo, n, nrhs, a, lda, ipiv, b, ldb, info)

CHETRS — that's her, that's the icon 👑

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🦋 Function/Subroutine Documentation 🦋

subroutine CHETRS (character uplo, integer n, integer nrhs, complex,
    dimension( lda, * ) a, integer lda, integer, dimension( * ) ipiv,
    complex, dimension( ldb, * ) b, integer ldb, integer info)

CHETRS 💅 (yes they really do write the name twice, it's giving main character energy fr fr)

🎀 Purpose

!> CHETRS solves a system of linear equations A*X = B with a complex Hermitian matrix A using the factorization A = U*D*UH or A = L*D*LH computed by CHETRF.

so basically: you already did the whole factorization thing with CHETRF, and now she's here to actually solve A*X = B for you, where A is a complex Hermitian matrix 🌈. You don't redo the factorization, you just hand her the pieces and she handles the rest. obsessed honestly 🫶

🧚 Parameters

💜 UPLO

UPLO is CHARACTER*1 — it tells her whether the factorization details are chilling as an upper or lower triangular matrix ✨

• = 'U' — upper triangular, and the form is A = U*D*U**H
• = 'L' — lower triangular, and the form is A = L*D*L**H

pick one, bestie, those are literally the two options 🎀

💜 N

N is INTEGER — the order of the matrix A, and N >= 0 ⭐

💜 NRHS

NRHS is INTEGER — the number of right hand sides, aka the number of columns of the matrix B, and NRHS >= 0 🦋

💜 A

A is COMPLEX array, dimension (LDA,N) — this is where the block diagonal matrix D lives, plus the multipliers used to get the factor U or L, exactly as computed by CHETRF 👑

💜 LDA

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

💜 IPIV

IPIV is INTEGER array, dimension (N) — the deets on the interchanges and the block structure of D, as determined by CHETRF 🔥

💜 B

B is COMPLEX array, dimension (LDB,NRHS) 🌸

• on entry: the right hand side matrix B
• on exit: the solution matrix X

she literally swaps it in place, iconic behaviour, no cap 💀

💜 LDB

LDB is INTEGER — the leading dimension of the array B, and LDB >= max(1,N) ✨

💜 INFO

INFO is INTEGER — the vibe report 😌

• = 0 — successful exit, slay 🎉
• < 0 — if INFO = -i, the i-th argument had an illegal value 🙈

🫶 Author

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

Definition at line 119 of file chetrs.f. 📍

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👑 Author

Generated automatically by Doxygen for LAPACK from the source code 🤖✨ (she didn't write her own bio, the robots did it for her)

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and that's the whole page, bestie 💖 this was brought to you by LAPACK Version 3.12.0, living at /home/abui...RC/chetrs.f(3) — mwah, go solve something 🎀💅🦋