/home/abui.../chetrs2.f(3)

💅 NAME

okay so this page is literally /home/abui.../chetrs2.f(3) from the Library Functions Manual, and bestie the star of the show is:

/home/abuild/rpmbuild/BUILD/lapack-
static-3.12.0-build/lapack-3.12.0/SRC/chetrs2.f

that's the file, that's the whole path, no I'm not abbreviating it, it's giving full government name energy 🫶

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✨ SYNOPSIS

🌸 Functions/Subroutines

subroutine CHETRS2 (uplo, n, nrhs, a, lda, ipiv, b, ldb, work, info)
    CHETRS2

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🦋 Function/Subroutine Documentation

🎀 the signature, in full, no cuts

subroutine CHETRS2 (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)
    CHETRS2

🌈 Purpose:

!>
!> CHETRS2 solves a system of linear equations A*X = B with a complex
!> Hermitian matrix A using the factorization A = U*D*U**H or
!> A = L*D*L**H computed by CHETRF and converted by CSYCONV.
!>

okay so translate that for the girlies: you've got a system A*X = B, A is a complex Hermitian matrix (iconic, self-adjoint, we love her), and she was already factored as A = U*D*U**H or A = L*D*L**H — done by CHETRF, then converted by CSYCONV. CHETRS2 just takes that factorization and actually solves the thing. periodt. 💅

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🌸 Parameters

• UPLO — UPLO is CHARACTER*1. tells us whether the factorization details are chillin' in an upper or lower triangular matrix. = 'U': upper triangular, form is A = U*D*U**H; = 'L': lower triangular, form is A = L*D*L**H. pick one bestie, and pick it correctly 😤
• N — N is INTEGER, the order of the matrix A. constraint: N >= 0. no negative orders, that's not a vibe. ✨
• NRHS — NRHS is INTEGER, the number of right hand sides, i.e. the number of columns of the matrix B. constraint: NRHS >= 0. again, zero or more, we don't do negative. 🎀
• A — A is COMPLEX 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 CHETRF. already cooked, don't re-cook it. 🔥
• LDA — LDA is INTEGER, the leading dimension of the array A. constraint: LDA >= max(1,N). respect the leading dimension or suffer 🙈
• IPIV — IPIV is INTEGER array, dimension (N). details of the interchanges and the block structure of D, as determined by CHETRF. the receipts, basically. 🧾
• B — B is COMPLEX array, dimension (LDB,NRHS). on entry, the right hand side matrix B. on exit, the solution matrix X. she comes in as the problem and leaves as the answer, main character transformation fr fr 👑
• LDB — LDB is INTEGER, the leading dimension of the array B. constraint: LDB >= max(1,N). same rule, different array, don't skip it. 💜
• WORK — WORK is COMPLEX array, dimension (N). scratch space, does the work, gets no credit. the intern of arrays. 😭
• INFO — INFO is INTEGER. = 0: successful exit, slay 🎉; < 0: if INFO = -i, the i-th argument had an illegal value, so like… you fed her something bad, check your arguments. 💀

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🫶 Author

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

🧚 Definition at line 125 of file chetrs2.f.

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⭐ Author

Generated automatically by Doxygen for LAPACK from the source code. (not a human, not a vibe curator, just a doc generator doing its thing ✨)

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🌸 and that's the whole page bestie, no notes, go solve your Hermitian systems responsibly 💖

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sign-off time: this is LAPACK, Version 3.12.0, page /home/abui.../chetrs2.f(3) — mwah, take care of her 🎀🦋💅