SRC/slaqz4.f(3)            Library Functions Manual            SRC/slaqz4.f(3)

NAME
       SRC/slaqz4.f

SYNOPSIS
   Functions/Subroutines
       subroutine slaqz4 (ilschur, ilq, ilz, n, ilo, ihi, nshifts,
           nblock_desired, sr, si, ss, a, lda, b, ldb, q, ldq, z, ldz, qc,
           ldqc, zc, ldzc, work, lwork, info)
           SLAQZ4

Function/Subroutine Documentation
   subroutine slaqz4 (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) nshifts, integer,
       intent(in) nblock_desired, real, dimension( * ), intent(inout) sr,
       real, dimension( * ), intent(inout) si, real, dimension( * ),
       intent(inout) ss, real, dimension( lda, * ), intent(inout) a, integer,
       intent(in) lda, real, dimension( ldb, * ), intent(inout) b, integer,
       intent(in) ldb, real, dimension( ldq, * ), intent(inout) q, integer,
       intent(in) ldq, real, dimension( ldz, * ), intent(inout) z, integer,
       intent(in) ldz, real, dimension( ldqc, * ), intent(inout) qc, integer,
       intent(in) ldqc, real, dimension( ldzc, * ), intent(inout) zc, integer,
       intent(in) ldzc, real, dimension( * ), intent(inout) work, integer,
       intent(in) lwork, integer, intent(out) info)
       SLAQZ4

       Purpose:


           !>
           !> SLAQZ4 Executes a single multishift QZ sweep
           !>

       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
           !>

           NSHIFTS

           !>          NSHIFTS is INTEGER
           !>          The desired number of shifts to use
           !>

           NBLOCK_DESIRED

           !>          NBLOCK_DESIRED is INTEGER
           !>          The desired size of the computational windows
           !>

           SR

           !>          SR is REAL array. SR contains
           !>          the real parts of the shifts to use.
           !>

           SI

           !>          SI is REAL array. SI contains
           !>          the imaginary parts of the shifts to use.
           !>

           SS

           !>          SS is REAL array. SS contains
           !>          the scale of the shifts to use.
           !>

           A

           !>          A is REAL array, dimension (LDA, N)
           !>

           LDA

           !>          LDA is INTEGER
           !>          The leading dimension of the array A.  LDA >= max( 1, N ).
           !>

           B

           !>          B is REAL array, dimension (LDB, N)
           !>

           LDB

           !>          LDB is INTEGER
           !>          The leading dimension of the array B.  LDB >= max( 1, N ).
           !>

           Q

           !>          Q is REAL array, dimension (LDQ, N)
           !>

           LDQ

           !>          LDQ is INTEGER
           !>

           Z

           !>          Z is REAL array, dimension (LDZ, N)
           !>

           LDZ

           !>          LDZ is INTEGER
           !>

           QC

           !>          QC is REAL array, dimension (LDQC, NBLOCK_DESIRED)
           !>

           LDQC

           !>          LDQC is INTEGER
           !>

           ZC

           !>          ZC is REAL array, dimension (LDZC, NBLOCK_DESIRED)
           !>

           LDZC

           !>          LDZ is INTEGER
           !>

           WORK

           !>          WORK is REAL 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.
           !>

           INFO

           !>          INFO is INTEGER
           !>          = 0: successful exit
           !>          < 0: if INFO = -i, the i-th argument had an illegal value
           !>

       Author
           Thijs Steel, KU Leuven

       Date
           May 2020

       Definition at line 210 of file slaqz4.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

LAPACK                          Version 3.12.0                 SRC/slaqz4.f(3)