TESTING/EIG/cget54.f(3)

🎀 TESTING/EIG/cget54.f(3) 🎀

Bestie, welcome to the Library Functions Manual page for TESTING/EIG/cget54.f. This is the cget54 subroutine, and it's literally giving decomposition-verification main character energy. 💅✨

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🌸 NAME 🌸

TESTING/EIG/cget54.f

🦋 SYNOPSIS 🦋

Functions/Subroutines 🫶

subroutine cget54 (n, a, lda, b, ldb, s, lds, t, ldt, u, ldu, v, ldv,
           work, result)
           CGET54

🔥 Function/Subroutine Documentation 🔥

subroutine cget54 (integer n, complex, dimension( lda, * ) a, integer lda,
       complex, dimension( ldb, * ) b, integer ldb, complex, dimension( lds, *
       ) s, integer lds, complex, dimension( ldt, * ) t, integer ldt, complex,
       dimension( ldu, * ) u, integer ldu, complex, dimension( ldv, * ) v,
       integer ldv, complex, dimension( * ) work, real result)
       CGET54

Purpose 💖

Okay so CGET54 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. Obsessed. 🫶

Specifically,

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

💜 Parameters 💜

• N — N is INTEGER. It's the size of the matrix. If it is zero, SGET54 does nothing. It must be at least zero. (Yep, that's SGET54 in the original — keeping it exactly like that, no cap. 👀)
• A — A is COMPLEX array, dimension (LDA, N). It's 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 array, dimension (LDB, N). It's 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 array, dimension (LDS, N). It's 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 array, dimension (LDT, N). It's 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 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 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 array, dimension (3*N**2).
• RESULT — RESULT is REAL. 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 cget54.f.

👑 Author 👑 (the auto-generated one)

Generated automatically by Doxygen for LAPACK from the source code.

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Okay bestie, that's the whole page. Cute sign-off: this iconic page is for LAPACK Version 3.12.0 and TESTING/EIG/cget54.f(3). Stay slay, verify your decompositions, and hydrate. 💖✨🎀