TESTING/LIN/cqrt12.f(3)

💅 TESTING/LIN/cqrt12.f 💅

okay so bestie, welcome to the cqrt12 page from the LAPACK manual (you're in the TESTING/LIN directory btw, slay) — it's a Fortran file, it's iconic, and it's lowkey doing some very specific math for us 💖

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✨ SYNOPSIS ✨

🎀 Functions/Subroutines 🎀

• real function cqrt12 (m, n, a, lda, s, work, lwork, rwork) — CQRT12

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🦋 Function/Subroutine Documentation 🦋

real function cqrt12 (integer m, integer n, complex, dimension( lda, * ) a,
    integer lda, real, dimension( * ) s, complex, dimension( lwork ) work,
    integer lwork, real, dimension( * ) rwork)

CQRT12 💫

🌸 Purpose: 🌸

!> CQRT12 computes the singular values `svlues' of the upper trapezoid !> of A(1:M,1:N) and returns the ratio !> || svlues -s ||/( ||s||*eps*max(M,N) )

like yes, it literally computes those svlues (that spelling is straight from the source, don't come for me 😭) of the upper trapezoid of A(1:M,1:N) and hands you back that ratio. periodt. 🔥

🌈 Parameters 🌈

• M

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

it's the row count bestie, the number of rows of the matrix A 👑

• N

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

the column count — the number of columns of the matrix A 🫶

• A

!> A is COMPLEX array, dimension (LDA,N) !> The M-by-N matrix A. Only the upper trapezoid is referenced.

your M-by-N matrix A — and heads up, only the upper trapezoid gets referenced, the rest is just vibing 🙈

• LDA

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

the leading dimension of the array A, no cap 🧚

• S

!> S is REAL array, dimension (min(M,N)) !> The singular values of the matrix A.

REAL array of dimension min(M,N) holding the singular values of the matrix A ⭐

• WORK

!> WORK is COMPLEX array, dimension (LWORK)

COMPLEX array, dimension (LWORK) — it's the workspace, it's doing the work, main character energy honestly 💀

• LWORK

!> LWORK is INTEGER !> The length of the array WORK. LWORK >= M*N + 2*min(M,N) + !> max(M,N).

the length of the array WORK, and the vibe check here is real: LWORK >= M*N + 2*min(M,N) + max(M,N) — don't skimp on it 🎀

• RWORK

!> RWORK is REAL array, dimension (4*min(M,N))

REAL array, dimension (4*min(M,N)) — yes, four times, that's not a typo 🌸

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👑 Author 👑

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

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Definition at line 95 of file cqrt12.f. 📍

💜 Author 💜

Generated automatically by Doxygen for LAPACK from the source code. (the robots wrote this part, not me 🫡)

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okay that's the whole page bestie, you ate that 🍓

LAPACK — Version 3.12.0 🌈💅✨ sign-off, with the page tag TESTING/LIN/cqrt12.f(3) — go be iconic with your singular values fr fr 💖🦋🎀