TESTING/EIG/zget54.f(3)

💖 TESTING/EIG/zget54.f(3) 💖

okay so this is the TESTING/EIG/zget54.f(3) page from the Library Functions Manual — welcome to the group chat, bestie 💅

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✨ NAME ✨

TESTING/EIG/zget54.f — the page for ZGET54, and no cap, it's giving “test routine for a generalized decomposition” energy 🦋

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🌸 SYNOPSIS 🌸

Functions/Subroutines

• subroutine zget54 (n, a, lda, b, ldb, s, lds, t, ldt, u, ldu, v, ldv, work, result) — ZGET54

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🎀 Function/Subroutine Documentation 🎀

subroutine zget54 ( integer n, complex*16, dimension( lda, * ) a, integer
    lda, complex*16, dimension( ldb, * ) b, integer ldb, complex*16,
    dimension( lds, * ) s, integer lds, complex*16, dimension( ldt, * ) t,
    integer ldt, complex*16, dimension( ldu, * ) u, integer ldu, complex*16,
    dimension( ldv, * ) v, integer ldv, complex*16, dimension( * ) work,
    double precision result )

ZGET54

🦋 Purpose 🦋

okay so ZGET54 checks a generalized decomposition of the form

A = U*S*V'  and B = U*T* V'

where ' means conjugate transpose and U and V are unitary. literally iconic.

Specifically,

RESULT = ||( A - U*S*V', B - U*T*V' )|| / (||( A, B )||*n*ulp )

💜 Parameters 💜

• N — N is INTEGER. The size of the matrix. If it is zero, DGET54 does nothing. It must be at least zero. 🫶
• A — A is COMPLEX*16 array, dimension (LDA, N). The original (unfactored) matrix A.
• LDA — LDA is INTEGER. The leading dimension of A. It must be at least 1 and at least N.
• B — B is COMPLEX*16 array, dimension (LDB, N). The original (unfactored) matrix B.
• LDB — LDB is INTEGER. The leading dimension of B. It must be at least 1 and at least N.
• S — S is COMPLEX*16 array, dimension (LDS, N). The factored matrix S.
• LDS — LDS is INTEGER. The leading dimension of S. It must be at least 1 and at least N.
• T — T is COMPLEX*16 array, dimension (LDT, N). The factored matrix T.
• LDT — LDT is INTEGER. The leading dimension of T. It must be at least 1 and at least N.
• U — U is COMPLEX*16 array, dimension (LDU, N). The orthogonal matrix on the left-hand side in the decomposition.
• LDU — LDU is INTEGER. The leading dimension of U. LDU must be at least N and at least 1.
• V — V is COMPLEX*16 array, dimension (LDV, N). The orthogonal matrix on the left-hand side in the decomposition.
• LDV — LDV is INTEGER. The leading dimension of V. LDV must be at least N and at least 1.
• WORK — WORK is COMPLEX*16 array, dimension (3*N**2).
• RESULT — RESULT is DOUBLE PRECISION. The value RESULT, It is currently limited to 1/ulp, to avoid overflow. Errors are flagged by RESULT=10/ulp.

👑 Author 👑

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

Definition at line 154 of file zget54.f.

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🫶 Author 🫶

Generated automatically by Doxygen for LAPACK from the source code.

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cute sign-off: this page is from the LAPACK source code, Version 3.12.0 — and the footer doesn’t list a date, so I’m not inventing one, bestie; just the TESTING/EIG/zget54.f(3) page tag 💖✨