/home/abui.../csytrs2.f(3)

🦋 csytrs2.f(3) 🦋

okay so bestie, this page is from the Library Functions Manual, and it's literally all about the Fortran file csytrs2.f. no cap, it's a LAPACK thing and it's giving iconic linear algebra energy. ✨

✨ NAME ✨

the name is just the whole file path, bestie: /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/csytrs2.f — periodt. 💅

🌸 SYNOPSIS 🌸

Functions/Subroutines

• subroutine CSYTRS2 (uplo, n, nrhs, a, lda, ipiv, b, ldb, work, info) — CSYTRS2

💖 Function/Subroutine Documentation 💖

🫶 subroutine CSYTRS2 🫶

subroutine CSYTRS2 (character uplo, integer n, integer nrhs, complex, dimension( lda, * ) a, integer lda, integer, dimension( * ) ipiv, complex, dimension( ldb, * ) b, integer ldb, complex, dimension( * ) work, integer info)

CSYTRS2

🎀 Purpose 🎀

okay so CSYTRS2 solves a system of linear equations A*X = B with a complex symmetric matrix A using the factorization A = U*D*U**T or A = L*D*L**T computed by CSYTRF and converted by CSYCONV. it's literally doing the most and we love her for it. 💅

🌈 Parameters 🌈

💜 UPLO

UPLO is CHARACTER*1 — it tells you whether the details of the factorization are stored as an upper or lower triangular matrix.

• = 'U': Upper triangular, form is A = U*D*U**T;
• = 'L': Lower triangular, form is A = L*D*L**T.

🦋 N

N is INTEGER — the order of the matrix A. N >= 0. slay.

🍓 NRHS

NRHS is INTEGER — the number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0.

🌸 A

A is COMPLEX array, dimension (LDA,N) — the block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by CSYTRF.

ngl, A is input / output. this might be counter-intuitive, and one may think that A is input only. but A is input / output. this is because, at the start of the subroutine, we permute A in a form and then we permute A back to its original form at the end. so yeah, she's doing a little costume change and then changing back. 🎭

🧚 LDA

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

🔥 IPIV

IPIV is INTEGER array, dimension (N) — details of the interchanges and the block structure of D as determined by CSYTRF.

👑 B

B is COMPLEX array, dimension (LDB,NRHS) — on entry, the right hand side matrix B. on exit, the solution matrix X. she's a main character who gets a glow-up. ✨

⭐ LDB

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

💀 WORK

WORK is COMPLEX array, dimension (N) — that's it, that's the whole vibe.

🙈 INFO

INFO is INTEGER — here's the tea:

• = 0: successful exit
• < 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 130 of file csytrs2.f.

🌟 Author 🌟

Generated automatically by Doxygen for LAPACK from the source code. (yes, the robot wrote this part, we love a consistent queen. 🤖💅)

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and that's the whole page, bestie! 🫶 this was LAPACK Version 3.12.0, from /home/abui.../csytrs2.f(3) — mwah! 🎀✨🌈