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

🦋 NAME 🦋

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/ssytrs_rook.f

okay so bestie, that's a whole file path and yes it's coming in as the name, no we're not gonna argue with it. it's the Fortran source file for SSYTRS_ROOK, from the lapack-static-3.12.0-build, and it lives in lapack-3.12.0/SRC/ 💅. that's the whole vibe check.

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✨ SYNOPSIS ✨

🌸 Functions/Subroutines 🌸

• subroutine SSYTRS_ROOK (uplo, n, nrhs, a, lda, ipiv, b, ldb, info) — that's our girl. SSYTRS_ROOK. iconic name, honestly.

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💖 Function/Subroutine Documentation 💖

🎀 the actual signature 🎀

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

SSYTRS_ROOK — she's back and she's solving things 🫶

⭐ Purpose ⭐

okay so, no cap, here's what she does:

!>
!> SSYTRS_ROOK solves a system of linear equations A*X = B with
!> a real symmetric matrix A using the factorization A = U*D*U**T or
!> A = L*D*L**T computed by SSYTRF_ROOK.
!>

so like — she solves A*X = B, where A is a real symmetric matrix, and she's building off the factorization A = U*D*U**T or A = L*D*L**T that SSYTRF_ROOK already did. she's not doing the heavy lifting from scratch, she's finishing the job. main character energy fr fr 👑

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🧚 Parameters 🧚

• UPLO — UPLO is CHARACTER*1, and she tells you whether the factorization details are stored as an upper or lower triangular matrix, periodt:
  • = '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. constraint: N >= 0. keep it non-negative bestie, that's the rule 💀
• NRHS — NRHS is INTEGER. the number of right hand sides — like, the number of columns of the matrix B. constraint: NRHS >= 0.
• A — A is REAL array, dimension (LDA,N). this is the block diagonal matrix D plus the multipliers used to obtain the factor U or L, exactly as computed by SSYTRF_ROOK. she's inheriting this from her sister function, iykyk 🌈
• LDA — LDA is INTEGER. the leading dimension of the array A. constraint: LDA >= max(1,N).
• IPIV — IPIV is INTEGER array, dimension (N). the details of the interchanges and the block structure of D, as determined by SSYTRF_ROOK. again — SSYTRF_ROOK set this up, we're just reading it 🍓
• B — B is REAL array, dimension (LDB,NRHS). on entry, the right hand side matrix B. on exit, the solution matrix X. literally the glow-up moment of this whole routine: B walks in as the problem and leaves as the answer 💅✨
• LDB — LDB is INTEGER. the leading dimension of the array B. constraint: LDB >= max(1,N).
• INFO — INFO is INTEGER, the receipts:
  • = 0: successful exit 🎉
  • < 0: if INFO = -i, the i-th argument had an illegal value 😭

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👑 Author 👑

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

four institutions, one legend. we stan an academic collaboration 🫶

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🦋 Contributors: 🦋

!>
!>   April 2012, Igor Kozachenko,
!>                  Computer Science Division,
!>                  University of California, Berkeley
!>
!>  September 2007, Sven Hammarling, Nicholas J. Higham, Craig Lucas,
!>                  School of Mathematics,
!>                  University of Manchester
!>
!>

shoutout to Igor Kozachenko (April 2012, Computer Science Division, University of California, Berkeley) and to Sven Hammarling, Nicholas J. Higham, and Craig Lucas (September 2007, School of Mathematics, University of Manchester) — we love a credited squad 🌸🧚

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🔥 Definition at line 134 of file ssytrs_rook.f. 🔥

that's where the magic literally starts. line one-three-four, mark it.

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💜 Author 💜

Generated automatically by Doxygen for LAPACK from the source code. yes, a robot wrote this page. she's still slaying though 🙈

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and that's the whole thing, bestie 💖 written to you by LAPACK, Version 3.12.0, dated /home/abui...trs_rook.f(3) — no cap, that's the sign-off, go solve some linear systems ✨🎀