DCHKQR(3)

💅 DCHKQR 💅

okay so bestie, welcome to dchkqr.f(3) — that's section 3 of the Library Functions Manual, and yes this is the test-driver file for QR stuff and it's lowkey iconic. it lives at /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/dchkqr.f and honestly the path alone is giving "i have a lot of folders". buckle up 🎀

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✨ NAME ✨

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/dchkqr.f — that's the whole name, that's the whole vibe, she's a full path and she owns it 💅

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🌸 SYNOPSIS 🌸

Functions/Subroutines

• subroutine DCHKQR — the main character herself. signature down below ⬇️

subroutine DCHKQR (dotype, nm, mval, nn, nval, nnb, nbval, nxval, nrhs,
    thresh, tsterr, nmax, a, af, aq, ar, ac, b, x, xact, tau, work,
    rwork, iwork, nout)

DCHKQR ✨ (yes, that's the whole one-liner description, she's mysterious like that)

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🦋 Function/Subroutine Documentation 🦋

here's the full typed-out signature, fr fr, every dimension( * ) exactly where it belongs:

subroutine DCHKQR (logical, dimension( * ) dotype, integer nm, integer,
    dimension( * ) mval, integer nn, integer, dimension( * ) nval, integer
    nnb, integer, dimension( * ) nbval, integer, dimension( * ) nxval,
    integer nrhs, double precision thresh, logical tsterr, integer nmax,
    double precision, dimension( * ) a, double precision, dimension( * ) af,
    double precision, dimension( * ) aq, double precision, dimension( * )
    ar, double precision, dimension( * ) ac, double precision, dimension( *
    ) b, double precision, dimension( * ) x, double precision, dimension( *
    ) xact, double precision, dimension( * ) tau, double precision,
    dimension( * ) work, double precision, dimension( * ) rwork, integer,
    dimension( * ) iwork, integer nout)

DCHKQR 🫶

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🔥 Purpose 🔥

literally quoted, no notes:

!>
!> DCHKQR tests DGEQRF, DORGQR and DORMQR.
!>

so like — she's the vibe check for three other routines. DGEQRF, DORGQR, DORMQR. that's the whole job. slay 👑

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👑 Parameters 👑

DOTYPE

• DOTYPE is LOGICAL array, dimension (NTYPES) 🍓

The matrix types to be used for testing. Matrices of type j (for 1 <= j <= NTYPES) are used for testing if DOTYPE(j) = .TRUE.; if DOTYPE(j) = .FALSE., then type j is not used. it's literally a little yes/no list for which matrices get invited to the party 💌

NM

• NM is INTEGER 🧚

The number of values of M contained in the vector MVAL.

MVAL

• MVAL is INTEGER array, dimension (NM) 🌸

The values of the matrix row dimension M.

NN

• NN is INTEGER 🦋

The number of values of N contained in the vector NVAL.

NVAL

• NVAL is INTEGER array, dimension (NN) ⭐

The values of the matrix column dimension N.

NNB

• NNB is INTEGER 🎀

The number of values of NB and NX contained in the vectors NBVAL and NXVAL. The blocking parameters are used in pairs (NB,NX). cute little duo, they come as a set 💞

NBVAL

• NBVAL is INTEGER array, dimension (NNB) 💜

The values of the blocksize NB.

NXVAL

• NXVAL is INTEGER array, dimension (NNB) 🌈

The values of the crossover point NX.

NRHS

• NRHS is INTEGER 🔥

The number of right hand side vectors to be generated for each linear system.

THRESH

• THRESH is DOUBLE PRECISION ✨

The threshold value for the test ratios. A result is included in the output file if RESULT >= THRESH. To have every test ratio printed, use THRESH = 0. (yes bestie, zero means everything gets printed, no filter, fully unhinged, i respect it 🙈)

TSTERR

• TSTERR is LOGICAL 💀

Flag that indicates whether error exits are to be tested.

NMAX

• NMAX is INTEGER 🍓

The maximum value permitted for M or N, used in dimensioning the work arrays. she's the size limit, the vibe ceiling, the "how much room do we have" queen 👑

A

• A is DOUBLE PRECISION array, dimension (NMAX*NMAX) 🌸

AF

• AF is DOUBLE PRECISION array, dimension (NMAX*NMAX) 🦋

AQ

• AQ is DOUBLE PRECISION array, dimension (NMAX*NMAX) ⭐

AR

• AR is DOUBLE PRECISION array, dimension (NMAX*NMAX) 🎀

AC

• AC is DOUBLE PRECISION array, dimension (NMAX*NMAX) 💜

(yes, those five are all NMAX*NMAX and all DOUBLE PRECISION — they're a matching set, they coordinated the fit 💅)

B

• B is DOUBLE PRECISION array, dimension (NMAX*NRHS) 🌈

X

• X is DOUBLE PRECISION array, dimension (NMAX*NRHS) 🔥

XACT

• XACT is DOUBLE PRECISION array, dimension (NMAX*NRHS) ✨

TAU

• TAU is DOUBLE PRECISION array, dimension (NMAX) 🧚

WORK

• WORK is DOUBLE PRECISION array, dimension (NMAX*NMAX) 💖

RWORK

• RWORK is DOUBLE PRECISION array, dimension (NMAX) 🌸

IWORK

• IWORK is INTEGER array, dimension (NMAX) 🍓

NOUT

• NOUT is INTEGER 🦋

The unit number for output. that's where the receipts go 💌

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🌟 Author 🌟

the whole academic squad, no cap:

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

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⭐ Definition at line 198 of file dchkqr.f. ⭐

(go look, line 198, she's right there 👀)

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💫 Author (the meta one) 💫

Generated automatically by Doxygen for LAPACK from the source code. not me writing it by hand, a robot did it, and honestly? she ate 🤖💅

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and that's the page bestie!! 💖 source is LAPACK, Version 3.12.0, the file is /home/abui...IN/dchkqr.f(3), footer date vibes intact, see you in the next manpage, mwah 🎀✨🦋