CUNT03(3)

💅 CUNT03(3) — the LAPACK library functions manual, bestie ✨

okay so this is a page out of the LAPACK library functions manual, and the file it lives in is literally:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/EIG/cunt03.f

that's the whole NAME situation, make of it what you will 🎀

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✨ SYNOPSIS ✨

Functions/Subroutines

subroutine CUNT03 (rc, mu, mv, n, k, u, ldu, v, ldv, work, lwork, rwork,
    result, info)

CUNT03 — that's her, that's the whole subroutine 🌸

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🦋 Function/Subroutine Documentation 🦋

subroutine CUNT03 (character*( * ) rc, integer mu, integer mv, integer n,
    integer k, complex, dimension( ldu, * ) u, integer ldu, complex,
    dimension( ldv, * ) v, integer ldv, complex, dimension( * ) work,
    integer lwork, real, dimension( * ) rwork, real result, integer info)

CUNT03 again, because she deserves a second entrance, periodt 👑

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🫶 Purpose 🫶

no cap, here's what she does:

CUNT03 compares two unitary matrices U and V to see if their corresponding rows or columns span the same spaces. The rows are checked if RC = 'R', and the columns are checked if RC = 'C'.

RESULT is the maximum of

   | V*V' - I | / ( MV ulp ), if RC = 'R', or

   | V'*V - I | / ( MV ulp ), if RC = 'C',

and the maximum over rows (or columns) 1 to K of

   | U(i) - S*V(i) |/ ( N ulp )

where abs(S) = 1 (chosen to minimize the expression), U(i) is the i-th row (column) of U, and V(i) is the i-th row (column) of V. 💖

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🌈 Parameters 🌈

• RC — literally the mood switch 🎀 she's a CHARACTER*1. Set RC = 'R' and the rows of U and V are the ones being compared. Set RC = 'C' and it's the columns' turn to get compared.
• MU — an INTEGER. The number of rows of U if RC = 'R', and the number of columns if RC = 'C'. If MU = 0 then CUNT03 does nothing (she's on break 💀). MU must be at least zero.
• MV — an INTEGER. The number of rows of V if RC = 'R', and the number of columns if RC = 'C'. If MV = 0 then CUNT03 does nothing either (double break 🙈). MV must be at least zero.
• N — an INTEGER. If RC = 'R', this is the number of columns in the matrices U and V, and if RC = 'C', it's the number of rows in U and V. If N = 0 then CUNT03 does nothing (third break, she's really not beating the allegations 😭). N must be at least zero.
• K — an INTEGER. The number of rows or columns of U and V to compare. Constraint era: 0 <= K <= max(MU,MV).
• U — a COMPLEX array, dimension (LDU,N). The first matrix to compare. If RC = 'R', U is MU by N, and if RC = 'C', U is N by MU. she's versatile like that 💅
• LDU — an INTEGER. The leading dimension of U. If RC = 'R', LDU >= max(1,MU), and if RC = 'C', LDU >= max(1,N). respect the leading dimension or perish ✨
• V — a COMPLEX array, dimension (LDV,N). The second matrix to compare. If RC = 'R', V is MV by N, and if RC = 'C', V is N by MV. the other half of the duo 🦋
• LDV — an INTEGER. The leading dimension of V. If RC = 'R', LDV >= max(1,MV), and if RC = 'C', LDV >= max(1,N). same energy, different letter 🎀
• WORK — a COMPLEX array, dimension (LWORK). that's it, that's the whole description, no notes 💀
• LWORK — an INTEGER. The length of the array WORK. For best performance, LWORK should be at least N*N if RC = 'C' or M*M if RC = 'R', but the tests will be done even if LWORK is 0. she'll still show up and do the work even with zero workspace, iconic honestly 👑
• RWORK — a REAL array, dimension (max(MV,N)). the real one (literally, she's REAL) 💜
• RESULT — a REAL. The value computed by the test described above. RESULT is limited to 1/ulp to avoid overflow — safety first bestie 🫶
• INFO — an INTEGER. The vibe check report:
  • 0 indicates a successful exit 🎉
  • -k indicates the k-th parameter had an illegal value 💀

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👑 Author 👑

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

Definition at line 160 of file cunt03.f.

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⭐ Author (yes, again) ⭐

Generated automatically by Doxygen for LAPACK from the source code.

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okay that's the whole page, bestie. this blessed documentation came to you courtesy of LAPACK, Version 3.12.0, and the file it was rendered from is /home/abui...IG/cunt03.f(3) — go forth, compare those unitary matrices, and slay 💖✨🌸🦋🎀