CCKGSV(3)

💅 CCKGSV(3) — the cckgsv.f page, section 3 of the manual, bestie ✨

okay so real quick: this is a manual page from section 3 (that's the library-functions girlies 🎀), and the file it lives in is, like, deeply nested — no cap, look at this path:

/home/abuild/rpmbuild/BUILD/lapack-
static-3.12.0-build/lapack-3.12.0/TESTING/EIG/cckgsv.f

that's the NAME section btw. she's a whole address 💀

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🌈 SYNOPSIS 🌈

🌸 Functions/Subroutines 🌸

• subroutine CCKGSV (nm, mval, pval, nval, nmats, iseed, thresh, nmax, a, af, b, bf, u, v, q, alpha, beta, r, iwork, work, rwork, nin, nout, info) — CCKGSV ✨ (yes that's the whole description the original gave us and honestly? iconic minimalism 💅)

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🦋 Function/Subroutine Documentation 🦋

here's the full signature, and yes every single argument is listed, we are NOT skipping anybody, everyone's invited to the party 🫶

subroutine CCKGSV (integer nm, integer, dimension( * ) mval, integer,
    dimension( * ) pval, integer, dimension( * ) nval, integer nmats,
    integer, dimension( 4 ) iseed, real thresh, integer nmax, complex,
    dimension( * ) a, complex, dimension( * ) af, complex, dimension( * ) b,
    complex, dimension( * ) bf, complex, dimension( * ) u, complex,
    dimension( * ) v, complex, dimension( * ) q, real, dimension( * ) alpha,
    real, dimension( * ) beta, complex, dimension( * ) r, integer,
    dimension( * ) iwork, complex, dimension( * ) work, real, dimension( * )
    rwork, integer nin, integer nout, integer info)

CCKGSV 💖

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👑 Purpose: 👑

\ CCKGSV tests CGGSVD:\ the GSVD for M-by-N matrix A and P-by-N matrix B.\

like, she's a tester. her whole job is putting CGGSVD through its paces with an M-by-N matrix A and a P-by-N matrix B. main character energy fr fr 🔥

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✨ Parameters ✨

🍓 NM

NM is INTEGER\ The number of values of M contained in the vector MVAL.

so NM is just, like, how many M's we're bringing to the function. count 'em 💅

🍓 MVAL

MVAL is INTEGER array, dimension (NM)\ The values of the matrix row dimension M.

the actual M values themselves, bestie. row dimension of the matrix, one per slot 🌸

🍓 PVAL

PVAL is INTEGER array, dimension (NP)\ The values of the matrix row dimension P.

the P values — also row dimension, but for the other matrix. note the dimension says NP, that's what the page says, we don't editorialize 🙈

🍓 NVAL

NVAL is INTEGER array, dimension (NN)\ The values of the matrix column dimension N.

the N values! column dimension this time, she's different 💜

🍓 NMATS

NMATS is INTEGER\ The number of matrix types to be tested for each combination\ of matrix dimensions. If NMATS >= NTYPES (the maximum\ number of matrix types), then all the different types are\ generated for testing. If NMATS < NTYPES, another input line\ is read to get the numbers of the matrix types to be used.

OK so this one's got lore 🧚 — if NMATS >= NTYPES (that's the max number of matrix types) then every type gets generated for testing, slay. but if NMATS < NTYPES, she reads another input line to get the numbers of the matrix types to be used. dramatic much? 💀

🍓 ISEED

ISEED is INTEGER array, dimension (4)\ On entry, the seed of the random number generator. The array\ elements should be between 0 and 4095, otherwise they will be\ reduced mod 4096, and ISEED(4) must be odd.\ On exit, the next seed in the random number sequence after\ all the test matrices have been generated.

the ✨randomness✨ seed. on entry: the seed of the RNG. rules, bestie, rules:

• elements should be between 0 and 4095 — otherwise they get reduced mod 4096
• ISEED(4) must be odd

on exit? she gives you the next seed in the random number sequence after all the test matrices have been generated. a little gift 🎁

🍓 THRESH

THRESH is REAL\ 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.

the vibe check 💅 a result makes it into the output file only if RESULT >= THRESH. want every test ratio printed? set THRESH = 0. no filter, full transparency 🔥

🍓 NMAX

NMAX is INTEGER\ The maximum value permitted for M or N, used in dimensioning\ the work arrays.

the ceiling for M or N, and she's literally the reason the work arrays are sized the way they are. structural queen 👑

🍓 A

A is COMPLEX array, dimension (NMAX*NMAX)

🍓 AF

AF is COMPLEX array, dimension (NMAX*NMAX)

🍓 B

B is COMPLEX array, dimension (NMAX*NMAX)

🍓 BF

BF is COMPLEX array, dimension (NMAX*NMAX)

🍓 U

U is COMPLEX array, dimension (NMAX*NMAX)

🍓 V

V is COMPLEX array, dimension (NMAX*NMAX)

🍓 Q

Q is COMPLEX array, dimension (NMAX*NMAX)

seven COMPLEX girls, all dimension NMAX*NMAX, all absolutely holding it down 🫶

🍓 ALPHA

ALPHA is REAL array, dimension (NMAX)

(real one! different dimension! she's NMAX not NMAX*NMAX, respect the range 🌈)

🍓 BETA

BETA is REAL array, dimension (NMAX)

🍓 R

R is COMPLEX array, dimension (NMAX*NMAX)

🍓 IWORK

IWORK is INTEGER array, dimension (NMAX)

🍓 WORK

WORK is COMPLEX array, dimension (NMAX*NMAX)

🍓 RWORK

RWORK is REAL array, dimension (NMAX)

🍓 NIN

NIN is INTEGER\ The unit number for input.

where she reads from 📥

🍓 NOUT

NOUT is INTEGER\ The unit number for output.

where she writes to 📤 (the girlies who read the output file from THRESH, this is your address)

🍓 INFO

INFO is INTEGER\ = 0 : successful exit\ > 0 : If CLATMS returns an error code, the absolute value\ of it is returned.

the exit-status tea ☕

• = 0 → successful exit, we love a clean win 💖
• > 0 → if CLATMS returns an error code, the absolute value of it is returned (so, like, mask on, but the number's still feral 💀)

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🧚 Author 🧚

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

(the whole squad showed up, we stan a collab 🌈)

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⭐ Definition at line 195 of file cckgsv.f. ⭐

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🎀 Author 🎀

Generated automatically by Doxygen for LAPACK from the source code.

not me being auto-generated by Doxygen 😭 she's self-aware

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and that's the whole page, bestie — literally every flag, dimension, default and warning is up there, none skipped, periodt 💅✨

sign-off: this little beauty is LAPACK, Version 3.12.0, and she was living at /home/abui...IG/cckgsv.f(3) when we met her. take care of her 🫶🦋