!>
!> This routine is deprecated and has been replaced by routine ZGGES.
!>
!> ZGEGS computes the eigenvalues, Schur form, and, optionally, the
!> left and or/right Schur vectors of a complex matrix pair (A,B).
!> Given two square matrices A and B, the generalized Schur
!> factorization has the form
!>
!>    A = Q*S*Z**H,  B = Q*T*Z**H
!>
!> where Q and Z are unitary matrices and S and T are upper triangular.
!> The columns of Q are the left Schur vectors
!> and the columns of Z are the right Schur vectors.
!>
!> If only the eigenvalues of (A,B) are needed, the driver routine
!> ZGEGV should be used instead.  See ZGEGV for a description of the
!> eigenvalues of the generalized nonsymmetric eigenvalue problem
!> (GNEP).
!> 

JOBVSL

!>          JOBVSL is CHARACTER*1
!>          = 'N':  do not compute the left Schur vectors;
!>          = 'V':  compute the left Schur vectors (returned in VSL).
!> 

JOBVSR

!>          JOBVSR is CHARACTER*1
!>          = 'N':  do not compute the right Schur vectors;
!>          = 'V':  compute the right Schur vectors (returned in VSR).
!> 

N

!>          N is INTEGER
!>          The order of the matrices A, B, VSL, and VSR.  N >= 0.
!> 

A

!>          A is COMPLEX*16 array, dimension (LDA, N)
!>          On entry, the matrix A.
!>          On exit, the upper triangular matrix S from the generalized
!>          Schur factorization.
!> 

LDA

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

B

!>          B is COMPLEX*16 array, dimension (LDB, N)
!>          On entry, the matrix B.
!>          On exit, the upper triangular matrix T from the generalized
!>          Schur factorization.
!> 

LDB

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

ALPHA

!>          ALPHA is COMPLEX*16 array, dimension (N)
!>          The complex scalars alpha that define the eigenvalues of
!>          GNEP.  ALPHA(j) = S(j,j), the diagonal element of the Schur
!>          form of A.
!> 

BETA

!>          BETA is COMPLEX*16 array, dimension (N)
!>          The non-negative real scalars beta that define the
!>          eigenvalues of GNEP.  BETA(j) = T(j,j), the diagonal element
!>          of the triangular factor T.
!>
!>          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.
!> 

VSL

!>          VSL is COMPLEX*16 array, dimension (LDVSL,N)
!>          If JOBVSL = 'V', the matrix of left Schur vectors Q.
!>          Not referenced if JOBVSL = 'N'.
!> 

LDVSL

!>          LDVSL is INTEGER
!>          The leading dimension of the matrix VSL. LDVSL >= 1, and
!>          if JOBVSL = 'V', LDVSL >= N.
!> 

VSR

!>          VSR is COMPLEX*16 array, dimension (LDVSR,N)
!>          If JOBVSR = 'V', the matrix of right Schur vectors Z.
!>          Not referenced if JOBVSR = 'N'.
!> 

LDVSR

!>          LDVSR is INTEGER
!>          The leading dimension of the matrix VSR. LDVSR >= 1, and
!>          if JOBVSR = 'V', LDVSR >= N.
!> 

WORK

!>          WORK is COMPLEX*16 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(1,2*N).
!>          For good performance, LWORK must generally be larger.
!>          To compute the optimal value of LWORK, call ILAENV to get
!>          blocksizes (for ZGEQRF, ZUNMQR, and CUNGQR.)  Then compute:
!>          NB  -- MAX of the blocksizes for ZGEQRF, ZUNMQR, and CUNGQR;
!>          the optimal LWORK is N*(NB+1).
!>
!>          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 DOUBLE PRECISION array, dimension (3*N)
!> 

INFO

!>          INFO is INTEGER
!>          = 0:  successful exit
!>          < 0:  if INFO = -i, the i-th argument had an illegal value.
!>          =1,...,N:
!>                The QZ iteration failed.  (A,B) are not in Schur
!>                form, but ALPHA(j) and BETA(j) should be correct for
!>                j=INFO+1,...,N.
!>          > N:  errors that usually indicate LAPACK problems:
!>                =N+1: error return from ZGGBAL
!>                =N+2: error return from ZGEQRF
!>                =N+3: error return from ZUNMQR
!>                =N+4: error return from ZUNGQR
!>                =N+5: error return from ZGGHRD
!>                =N+6: error return from ZHGEQZ (other than failed
!>                                               iteration)
!>                =N+7: error return from ZGGBAK (computing VSL)
!>                =N+8: error return from ZGGBAK (computing VSR)
!>                =N+9: error return from ZLASCL (various places)
!> 

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