DLAQZ3(3)

🎀 NAME 🎀

okay bestie, this is the dlaqz3.f(3) page from the Library Functions Manual — and the NAME is literally this file path:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/dlaqz3.f

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✨ SYNOPSIS ✨

🌸 Functions/Subroutines 🌸

       recursive subroutine DLAQZ3 (ilschur, ilq, ilz, n, ilo, ihi, nw, a, lda,
           b, ldb, q, ldq, z, ldz, ns, nd, alphar, alphai, beta, qc, ldqc, zc,
           ldzc, work, lwork, rec, info)
           DLAQZ3

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💖 Function/Subroutine Documentation 💖

okay so the full recursive subroutine signature is right here, bestie — same vibes, every argument accounted for:

   recursive subroutine DLAQZ3 (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, double
       precision, dimension( lda, * ), intent(inout) a, integer, intent(in)
       lda, double precision, dimension( ldb, * ), intent(inout) b, integer,
       intent(in) ldb, double precision, dimension( ldq, * ), intent(inout) q,
       integer, intent(in) ldq, double precision, dimension( ldz, * ),
       intent(inout) z, integer, intent(in) ldz, integer, intent(out) ns,
       integer, intent(out) nd, double precision, dimension( * ), intent(inout)
       alphar, double precision, dimension( * ), intent(inout) alphai, double
       precision, dimension( * ), intent(inout) beta, double precision,
       dimension( ldqc, * ) qc, integer, intent(in) ldqc, double precision,
       dimension( ldzc, * ) zc, integer, intent(in) ldzc, double precision,
       dimension( * ) work, integer, intent(in) lwork, integer, intent(in) rec,
       integer, intent(out) info)
       DLAQZ3

🦋 Purpose 🦋

DLAQZ3 performs AED — that’s the whole Purpose section, no cap. 💅

🌈 Parameters 🌈

• ILSCHUR — logical, intent(in). ILSCHUR is LOGICAL. Determines whether or not to update the full Schur form.
• ILQ — logical, intent(in). ILQ is LOGICAL. Determines whether or not to update the matrix Q.
• ILZ — logical, intent(in). ILZ is LOGICAL. Determines whether or not to update the matrix Z.
• N — integer, intent(in). N is INTEGER. The order of the matrices A, B, Q, and Z. N >= 0.
• ILO — integer, intent(in). ILO is INTEGER.
• IHI — integer, intent(in). IHI is INTEGER. ILO and IHI mark the rows and columns of (A,B) which are to be normalized.
• NW — integer, intent(in). NW is INTEGER. The desired size of the deflation window.
• A — double precision, dimension (LDA, N), intent(inout). A is DOUBLE PRECISION array, dimension (LDA, N).
• LDA — integer, intent(in). LDA is INTEGER. The leading dimension of the array A. LDA >= max( 1, N ).
• B — double precision, dimension (LDB, N), intent(inout). B is DOUBLE PRECISION array, dimension (LDB, N).
• LDB — integer, intent(in). LDB is INTEGER. The leading dimension of the array B. LDB >= max( 1, N ).
• Q — double precision, dimension (LDQ, N), intent(inout). Q is DOUBLE PRECISION array, dimension (LDQ, N).
• LDQ — integer, intent(in). LDQ is INTEGER.
• Z — double precision, dimension (LDZ, N), intent(inout). Z is DOUBLE PRECISION array, dimension (LDZ, N).
• LDZ — integer, intent(in). LDZ is INTEGER.
• NS — integer, intent(out). NS is INTEGER. The number of unconverged eigenvalues available to use as shifts.
• ND — integer, intent(out). ND is INTEGER. The number of converged eigenvalues found.
• ALPHAR — double precision, dimension (N), intent(inout). ALPHAR is DOUBLE PRECISION array, dimension (N). The real parts of each scalar alpha defining an eigenvalue of GNEP.
• ALPHAI — double precision, dimension (N), intent(inout). ALPHAI is DOUBLE PRECISION array, dimension (N). The imaginary parts of each scalar alpha defining an eigenvalue of GNEP. If ALPHAI(j) is zero, then the j-th eigenvalue is real; if positive, then the j-th and (j+1)-st eigenvalues are a complex conjugate pair, with ALPHAI(j+1) = -ALPHAI(j).
• BETA — double precision, dimension (N), intent(inout). BETA is DOUBLE PRECISION array, dimension (N). The scalars beta that define the eigenvalues of GNEP. Together, the quantities alpha = (ALPHAR(j),ALPHAI(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 — double precision, dimension (LDQC, NW). QC is DOUBLE PRECISION array, dimension (LDQC, NW).
• LDQC — integer, intent(in). LDQC is INTEGER.
• ZC — double precision, dimension (LDZC, NW). ZC is DOUBLE PRECISION array, dimension (LDZC, NW).
• LDZC — integer, intent(in). The page’s own text here says LDZ is INTEGER — not LDZC, bestie, I’m just preserving it exactly. 💀
• WORK — double precision, dimension (MAX(1,LWORK)). WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK)). On exit, if INFO >= 0, WORK(1) returns the optimal LWORK.
• LWORK — integer, intent(in). 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.

• REC — integer, intent(in). REC is INTEGER. REC indicates the current recursion level. Should be set to 0 on first call.
• INFO — integer, intent(out). INFO is INTEGER.
  • = 0: successful exit
  • < 0: if INFO = -i, the i-th argument had an illegal value

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👑 Author — the human one 👑

Thijs Steel, KU Leuven

🌸 Date 🌸

May 2020

Definition at line 235 of file dlaqz3.f.

🤖 Author — generated one 🤖

Generated automatically by Doxygen for LAPACK from the source code.

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okay that’s the whole page, bestie 🫶 — LAPACK Version 3.12.0, dated May 2020, living at /home/abui...RC/dlaqz3.f(3). Periodt. 💅✨