/home/abui...D/cgelqs.f(3)

💅 NAME 💅

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

okay so that's the whole name, bestie — it's literally just the file path, no cap. This page comes from the Library Functions Manual and it's all about one iconic little deprecated LAPACK subroutine, so buckle up 🎀

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✨ SYNOPSIS ✨

Functions/Subroutines

subroutine CGELQS (m, n, nrhs, a, lda, tau, b, ldb, work, lwork, info)

CGELQS — that's her, that's the main character 👑

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🦋 Function/Subroutine Documentation 🦋

subroutine CGELQS (integer m, integer n, integer nrhs, complex, dimension(
    lda, * ) a, integer lda, complex, dimension( * ) tau, complex,
    dimension( ldb, * ) b, integer ldb, complex, dimension( lwork ) work,
    integer lwork, integer info)

CGELQS — again, same girl, now with her full parameter list on display 💖

🎯 Purpose:

!>
!> Compute a minimum-norm solution
!>     min || A*X - B ||
!> using the LQ factorization
!>     A = L*Q
!> computed by CGELQF.
!>

so basically: she computes a minimum-norm solution to min || A*X - B || using the LQ factorization A = L*Q that CGELQF already did the hard work for. teamwork, fr fr 🫶

🌸 Parameters 🌸

• M

!>          M is INTEGER
!>          The number of rows of the matrix A.  M >= 0.
!>

the number of rows of A. constraint: M >= 0 ✨

• N

!>          N is INTEGER
!>          The number of columns of the matrix A.  N >= M >= 0.
!>

the number of columns of A. constraint: N >= M >= 0 (yes, N is at least M, that's the vibe check she requires) 💅

• NRHS

!>          NRHS is INTEGER
!>          The number of columns of B.  NRHS >= 0.
!>

number of columns of B. constraint: NRHS >= 0 🎀

• A

!>          A is COMPLEX array, dimension (LDA,N)
!>          Details of the LQ factorization of the original matrix A as
!>          returned by CGELQF.
!>

a COMPLEX array of dimension (LDA,N) holding the details of the LQ factorization of the original A, exactly as CGELQF handed them back to you 🔥

• LDA

!>          LDA is INTEGER
!>          The leading dimension of the array A.  LDA >= M.
!>

leading dimension of A. constraint: LDA >= M ⭐

• TAU

!>          TAU is COMPLEX array, dimension (M)
!>          Details of the orthogonal matrix Q.
!>

COMPLEX array, dimension (M) — the deets on the orthogonal matrix Q 🧚

• B

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

COMPLEX array, dimension (LDB,NRHS). on entry she's the m-by-nrhs right hand side matrix B… on exit she's the n-by-nrhs solution matrix X. glow-up arc, honestly 😭💖

• LDB

!>          LDB is INTEGER
!>          The leading dimension of the array B. LDB >= N.
!>

leading dimension of B. constraint: LDB >= N 🦋

• WORK

!>          WORK is COMPLEX array, dimension (LWORK)
!>

COMPLEX array, dimension (LWORK) — the workspace, doing her quiet little job behind the scenes 🌸

• LWORK

!>          LWORK is INTEGER
!>          The length of the array WORK.  LWORK must be at least NRHS,
!>          and should be at least NRHS*NB, where NB is the block size
!>          for this environment.
!>

length of WORK. required: LWORK must be at least NRHS. recommended: it should be at least NRHS*NB, where NB is the block size for this environment. so like, do the first one or she'll be mad, do the second one or she'll be slow 💀

• INFO

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

the status report, always:

• = 0: successful exit — we love a clean run ✨
• < 0: if INFO = -i, the i-th argument had an illegal value — somebody misbehaved 🙈

👑 Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

(the legends behind the math, periodt 💜)

Definition at line 119 of file cgelqs.f.

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🌈 Author

Generated automatically by Doxygen for LAPACK from the source code. (not me, not you, Doxygen did this — iykyk 🎀)

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okay that's the whole page, bestie: LAPACK Version 3.12.0, from the file at /home/abui...D/cgelqs.f(3), dated with all that version-3.12.0 energy. go forth and factorize responsibly 💅✨🫶