ZLACSG(3)

okay so bestie 💅 welcome to zckcsd.f(3) — this is a page from the Library Functions Manual, and the header path is /home/abui...IG/zckcsd.f(3). It’s LAPACK testing code, which is highkey niche but lowkey iconic 🫶.

💖 NAME 💖

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

That’s the file, bestie: the zckcsd.f source file living deep in the LAPACK build tree. It’s giving “I was generated by a build system and I have lore” 📁✨.

✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

Two subroutines are serving here: ZCKCSD and ZLACSG. Their signatures are, exactly:

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

🎀 Function/Subroutine Documentation 🎀

💜 subroutine ZCKCSD 💜

Here’s the full typed signature of ZCKCSD, copied exactly because we do not mess with Fortran:

   subroutine ZCKCSD (integer nm, integer, dimension( * ) mval, integer,
       dimension( * ) pval, integer, dimension( * ) qval, integer nmats,
       integer, dimension( 4 ) iseed, double precision thresh, integer mmax,
       complex*16, dimension( * ) x, complex*16, dimension( * ) xf, complex*16,
       dimension( * ) u1, complex*16, dimension( * ) u2, complex*16, dimension(
       * ) v1t, complex*16, dimension( * ) v2t, double precision, dimension( *
       ) theta, integer, dimension( * ) iwork, complex*16, dimension( * ) work,
       double precision, dimension( * ) rwork, integer nin, integer nout,
       integer info)
       ZCKCSD

🦋 Purpose 🦋

ZCKCSD tests ZUNCSD: the CSD for an M-by-M unitary matrix X partitioned as [ X11 X12; X21 X22 ]. X11 is P-by-Q. That’s the whole purpose, and honestly it ate 💅.

🌸 Parameters 🌸

• 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.
• PVAL — PVAL is INTEGER array, dimension (NM). The values of the matrix row dimension P.
• QVAL — QVAL is INTEGER array, dimension (NM). The values of the matrix column dimension Q.
• 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.
• 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.
• 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.
• MMAX — MMAX is INTEGER. The maximum value permitted for M, used in dimensioning the work arrays.
• X — X is COMPLEX*16 array, dimension (MMAX*MMAX).
• XF — XF is COMPLEX*16 array, dimension (MMAX*MMAX).
• U1 — U1 is COMPLEX*16 array, dimension (MMAX*MMAX).
• U2 — U2 is COMPLEX*16 array, dimension (MMAX*MMAX).
• V1T — V1T is COMPLEX*16 array, dimension (MMAX*MMAX).
• V2T — V2T is COMPLEX*16 array, dimension (MMAX*MMAX).
• THETA — THETA is DOUBLE PRECISION array, dimension (MMAX).
• IWORK — IWORK is INTEGER array, dimension (MMAX).
• WORK — WORK is COMPLEX*16 array.
• RWORK — RWORK is DOUBLE PRECISION array.
• NIN — NIN is INTEGER. The unit number for input.
• NOUT — NOUT is INTEGER. The unit number for output.
• INFO — INFO is INTEGER. = 0: successful exit. > 0: If ZLAROR 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 zckcsd.f.

🧚 subroutine ZLACSG 🧚

   subroutine ZLACSG (integer m, integer p, integer q, double precision,
       dimension( * ) theta, integer, dimension( 4 ) iseed, complex*16,
       dimension( ldx, * ) x, integer ldx, complex*16, dimension( * ) work)

Definition at line 352 of file zckcsd.f.

💌 Author 💌

Generated automatically by Doxygen for LAPACK from the source code. 🤖💖

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Signed off with LAPACK Version 3.12.0 energy, page path /home/abui...IG/zckcsd.f(3) — and bestie, the footer does not show a date, so I’m not inventing one. No cap 💅✨