DCKCSD(3)

DCKCSD(3) 👑✨

okay so welcome to the LAPACK Library Functions Manual, bestie. This page is the official vibe check for /home/abui...IG/dckcsd.f(3) — yes, that header path with the little ... in it, no cap. It's all about the test routine DCKCSD and its sidekick DLACSG, and we're gonna go through every argument, every dimension, every tiny INTEGER, periodt. 💅

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NAME

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/EIG/dckcsd.f — that's the file, bestie. That long path is literally the NAME entry, and yes it's giving “I live in a build directory” main character energy. 🫶

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SYNOPSIS

Functions/Subroutines

Here's the signature lineup, copied exactly because we do not mess with code in this house:

subroutine DCKCSD (nm, mval, pval, qval, nmats, iseed, thresh, mmax, x,
    xf, u1, u2, v1t, v2t, theta, iwork, work, rwork, nin, nout, info)
    DCKCSD
subroutine DLACSG (m, p, q, theta, iseed, x, ldx, work)

DCKCSD is the big test routine, and DLACSG is the other subroutine chilling in the same file. Both iconic, both literally right there. 🌸

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Function/Subroutine Documentation

subroutine DCKCSD 🫶

Full signature, exactly as printed:

subroutine DCKCSD (integer nm, integer, dimension( * ) mval, integer,
    dimension( * ) pval, integer, dimension( * ) qval, integer nmats,
    integer, dimension( 4 ) iseed, double precision thresh, integer mmax,
    double precision, dimension( * ) x, double precision, dimension( * ) xf,
    double precision, dimension( * ) u1, double precision, dimension( * )
    u2, double precision, dimension( * ) v1t, double precision, dimension( *
    ) v2t, double precision, dimension( * ) theta, integer, dimension( * )
    iwork, double precision, dimension( * ) work, double precision,
    dimension( * ) rwork, integer nin, integer nout, integer info)
    DCKCSD

Purpose

DCKCSD tests DORCSD: the CSD for an M-by-M orthogonal matrix X partitioned as

[ X11 X12; X21 X22 ]

and X11 is P-by-Q. That's the whole point, and it ate. 💅

Parameters

• NM — INTEGER. The number of values of M contained in the vector MVAL.
• MVAL — INTEGER array, dimension (NM). The values of the matrix row dimension M.
• PVAL — INTEGER array, dimension (NM). The values of the matrix row dimension P.
• QVAL — INTEGER array, dimension (NM). The values of the matrix column dimension Q.
• NMATS — 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.
• ISEED — 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.
• THRESH — 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.
• MMAX — INTEGER. The maximum value permitted for M, used in dimensioning the work arrays.
• X — DOUBLE PRECISION array, dimension (MMAX*MMAX).
• XF — DOUBLE PRECISION array, dimension (MMAX*MMAX).
• U1 — DOUBLE PRECISION array, dimension (MMAX*MMAX).
• U2 — DOUBLE PRECISION array, dimension (MMAX*MMAX).
• V1T — DOUBLE PRECISION array, dimension (MMAX*MMAX).
• V2T — DOUBLE PRECISION array, dimension (MMAX*MMAX).
• THETA — DOUBLE PRECISION array, dimension (MMAX).
• IWORK — INTEGER array, dimension (MMAX).
• WORK — DOUBLE PRECISION array.
• RWORK — DOUBLE PRECISION array.
• NIN — INTEGER. The unit number for input.
• NOUT — INTEGER. The unit number for output.
• INFO — INTEGER.
  • = 0 : successful exit
  • > 0 : If DLAROR returns an error code, the absolute value of it is returned.

Author

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

Definition at line 181 of file dckcsd.f.

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subroutine DLACSG 🦋

Signature, exactly:

subroutine DLACSG (integer m, integer p, integer q, double precision,
    dimension( * ) theta, integer, dimension( 4 ) iseed, double precision,
    dimension( ldx, * ) x, integer ldx, double precision, dimension( * )
    work)

Definition at line 350 of file dckcsd.f.

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Author

Generated automatically by Doxygen for LAPACK from the source code. Not me hand-writing it at 2 a.m., fr fr. 💀

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cute sign-off time: the footer tag says LAPACK, Version 3.12.0, and the path /home/abui...IG/dckcsd.f(3). That's the source/version strip, bestie — no separate date is printed in this footer, so I'm not inventing one. Bye, slay, and may your dimensions always line up. 💖✨🎀