SRC/csytrs.f(3)

💅 SRC/csytrs.f

okay so this is the csytrs.f manual page, bestie — it lives in the SRC folder and it's giving "LAPACK Library Functions Manual" energy. buckle up 🎀

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✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine csytrs (uplo, n, nrhs, a, lda, ipiv, b, ldb, info) — literally the whole point of this page, it's CSYTRS 👑

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🦋 Function/Subroutine Documentation 🦋

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

CSYTRS — say it with me 💅

🌸 Purpose 🌸

!> !> CSYTRS 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. !>

so basically: you got a complex symmetric matrix A, you want A*X = B solved, and you're coming in with a factorization that CSYTRF already blessed you with. iconic handoff, no cap 🫶

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🎀 Parameters 🎀

UPLO

!> UPLO is CHARACTER*1 !> Specifies 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. !>

so UPLO is a CHARACTER*1 and it tells everyone whether the tea is stored upper or lower triangular. 'U' = upper triangular, form is A = U*D*U**T ⬆️. 'L' = lower triangular, form is A = L*D*L**T ⬇️. pick your fighter 💖

N

!> N is INTEGER !> The order of the matrix A. N >= 0. !>

N is an INTEGER, it's the order of the matrix A, and it has to be N >= 0. respectfully, negative orders are not invited to the function 🚫

NRHS

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

NRHS is an INTEGER = the number of right hand sides, aka the number of columns of the matrix B. also gotta be NRHS >= 0. we love a non-negative queen ✨

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. !>

A is a COMPLEX array, dimension (LDA,N). it holds the block diagonal matrix D plus the multipliers used to obtain the factor U or L, exactly as computed by CSYTRF. it's the whole lore of the factorization in one array 🔥

LDA

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

LDA is an INTEGER, the leading dimension of the array A, and it must satisfy LDA >= max(1,N). rules are rules bestie 💅

IPIV

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

IPIV is an INTEGER array, dimension (N), and it's carrying the details of the interchanges and the block structure of D, as determined by CSYTRF. it's the receipts 🧾

B

!> B is COMPLEX array, dimension (LDB,NRHS) !> On entry, the right hand side matrix B. !> On exit, the solution matrix X. !>

B is a COMPLEX array, dimension (LDB,NRHS). on entry it's the right hand side matrix B; on exit it's the solution matrix X. glow-up of the century honestly, main character energy 🌟

LDB

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

LDB is an INTEGER, the leading dimension of the array B, and yeah: LDB >= max(1,N). same vibe check as LDA 🦋

INFO

!> INFO is INTEGER !> = 0: successful exit !> < 0: if INFO = -i, the i-th argument had an illegal value !>

INFO is an INTEGER and it's the outcome report:

• = 0: successful exit 🎉 slay
• < 0: if INFO = -i, the i-th argument had an illegal value 💀 someone misbehaved

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👑 Author 👑

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

the academic supergroup fr fr 🫶

Definition at line 119 of file csytrs.f. 📍

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⭐ Author ⭐

Generated automatically by Doxygen for LAPACK from the source code. so it wrote itself, kind of a flex ngl 🤖✨

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and that's the page, bestie 💜 — brought to you by LAPACK, Version 3.12.0, dated right alongside SRC/csytrs.f(3). go solve something symmetric and complex, iykyk 🌈🍓