SRC/claqz2.f(3)

🎀 NAME 🎀

okay so this page is SRC/claqz2.f(3) from the Library Functions Manual, and the NAME is literally SRC/claqz2.f.

✨ SYNOPSIS ✨

🦋 Functions/Subroutines 🦋

recursive subroutine claqz2 (ilschur, ilq, ilz, n, ilo, ihi, nw, a, lda,
    b, ldb, q, ldq, z, ldz, ns, nd, alpha, beta, qc, ldqc, zc, ldzc,
    work, lwork, rwork, rec, info)

CLAQZ2

💅 Function/Subroutine Documentation 💅

recursive subroutine claqz2 (logical, intent(in) ilschur, logical,
    intent(in) ilq, logical, intent(in) ilz, integer, intent(in) n, integer,
    intent(in) ilo, integer, intent(in) ihi, integer, intent(in) nw,
    complex, dimension( lda, * ), intent(inout) a, integer, intent(in) lda,
    complex, dimension( ldb, * ), intent(inout) b, integer, intent(in) ldb,
    complex, dimension( ldq, * ), intent(inout) q, integer, intent(in) ldq,
    complex, dimension( ldz, * ), intent(inout) z, integer, intent(in) ldz,
    integer, intent(out) ns, integer, intent(out) nd, complex, dimension( *
    ), intent(inout) alpha, complex, dimension( * ), intent(inout) beta,
    complex, dimension( ldqc, * ) qc, integer, intent(in) ldqc, complex,
    dimension( ldzc, * ) zc, integer, intent(in) ldzc, complex, dimension( *
    ) work, integer, intent(in) lwork, real, dimension( * ) rwork, integer,
    intent(in) rec, integer, intent(out) info)

CLAQZ2

🌸 Purpose 🌸

bestie, the purpose is short and iconic: CLAQZ2 performs AED.

🧚 Parameters 🧚

• ILSCHUR — ILSCHUR is LOGICAL. Determines whether or not to update the full Schur form.
• ILQ — ILQ is LOGICAL. Determines whether or not to update the matrix Q.
• ILZ — ILZ is LOGICAL. Determines whether or not to update the matrix Z.
• N — N is INTEGER. The order of the matrices A, B, Q, and Z. N >= 0.
• ILO — ILO is INTEGER.
• IHI — IHI is INTEGER. ILO and IHI mark the rows and columns of (A,B) which are to be normalized.
• NW — NW is INTEGER. The desired size of the deflation window.
• A — A is COMPLEX array, dimension (LDA, N).
• LDA — LDA is INTEGER. The leading dimension of the array A. LDA >= max( 1, N ).
• B — B is COMPLEX array, dimension (LDB, N).
• LDB — LDB is INTEGER. The leading dimension of the array B. LDB >= max( 1, N ).
• Q — Q is COMPLEX array, dimension (LDQ, N).
• LDQ — LDQ is INTEGER.
• Z — Z is COMPLEX array, dimension (LDZ, N).
• LDZ — LDZ is INTEGER.
• NS — NS is INTEGER. The number of unconverged eigenvalues available to use as shifts.
• ND — ND is INTEGER. The number of converged eigenvalues found.
• ALPHA — ALPHA is COMPLEX array, dimension (N). Each scalar alpha defining an eigenvalue of GNEP.
• BETA — BETA is COMPLEX array, dimension (N). The scalars beta that define the eigenvalues of GNEP. Together, the quantities alpha = ALPHA(j) and beta = BETA(j) represent the j-th eigenvalue of the matrix pair (A,B), in one of the forms lambda = alpha/beta or mu = beta/alpha. Since either lambda or mu may overflow, they should not, in general, be computed.
• QC — QC is COMPLEX array, dimension (LDQC, NW).
• LDQC — LDQC is INTEGER.
• ZC — ZC is COMPLEX array, dimension (LDZC, NW).
• LDZC — LDZ is INTEGER.
• WORK — WORK is COMPLEX array, dimension (MAX(1,LWORK)). On exit, if INFO >= 0, WORK(1) returns the optimal LWORK.
• LWORK — LWORK is INTEGER. The dimension of the array WORK. LWORK >= max(1,N). If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this value as the first entry of the WORK array, and no error message related to LWORK is issued by XERBLA.
• RWORK — RWORK is REAL array, dimension (N).
• REC — REC is INTEGER. REC indicates the current recursion level. Should be set to 0 on first call.
• INFO — INFO is INTEGER. = 0: successful exit. < 0: if INFO = -i, the i-th argument had an illegal value.

👑 Author 👑

Thijs Steel, KU Leuven, KU Leuven

🎀 Date 🎀

May 2020

Definition at line 231 of file claqz2.f.

✨ Author ✨

Generated automatically by Doxygen for LAPACK from the source code.

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okay that's the whole page, bestie 💖 this was LAPACK Version 3.12.0, source page SRC/claqz2.f(3), dated May 2020 — slay and goodbye 🎀✨