*     F08PNF Example Program Text
*     Mark 21.  NAG Copyright 2004.
*     .. Parameters ..
      INTEGER          NIN, NOUT
      PARAMETER        (NIN=5,NOUT=6)
      INTEGER          NB, NMAX
      PARAMETER        (NB=64,NMAX=10)
      INTEGER          LDA, LDVS, LWORK
      PARAMETER        (LDA=NMAX,LDVS=NMAX,LWORK=NMAX+NMAX*NB)
*     .. Local Scalars ..
      INTEGER          I, IFAIL, INFO, J, LWKOPT, N, SDIM
*     .. Local Arrays ..
      COMPLEX *16      A(LDA,NMAX), VS(LDVS,NMAX), W(NMAX), WORK(LWORK)
      DOUBLE PRECISION RWORK(NMAX)
      LOGICAL          DUMMY(1)
      CHARACTER        CLABS(1), RLABS(1)
*     .. External Functions ..
      LOGICAL          F08PNZ
      EXTERNAL         F08PNZ
*     .. External Subroutines ..
      EXTERNAL         X04DBF, ZGEES
*     .. Executable Statements ..
      WRITE (NOUT,*) 'F08PNF Example Program Results'
      WRITE (NOUT,*)
*     Skip heading in data file
      READ (NIN,*)
      READ (NIN,*) N
      IF (N.LE.NMAX) THEN
*
*        Read the matrix A from data file
*
         READ (NIN,*) ((A(I,J),J=1,N),I=1,N)
*
*        Find the Schur factorization
*
         CALL ZGEES('Vectors (Schur)','No sort',F08PNZ,N,A,LDA,SDIM,W,
     +              VS,LDVS,WORK,LWORK,RWORK,DUMMY,INFO)
         LWKOPT = WORK(1)
*
         IF (INFO.GT.0) THEN
            WRITE (NOUT,99999) 'Failure in ZGEES. INFO =', INFO
         ELSE
*
*           Print out factors of the Schur factorization
*
            IFAIL = 0
            CALL X04DBF('General',' ',N,N,A,LDA,'Bracketed','F7.3',
     +                  'Schur matrix T','Integer',RLABS,'Integer',
     +                  CLABS,80,0,IFAIL)
*
            WRITE (NOUT,*)
            CALL X04DBF('General',' ',N,N,VS,LDVS,'Bracketed','F7.4',
     +                  'Matrix Z of Schur vectors','Integer',RLABS,
     +                  'Integer',CLABS,80,0,IFAIL)
         END IF
*
*        Print workspace information
*
         IF (LWORK.LT.LWKOPT) THEN
            WRITE (NOUT,*)
            WRITE (NOUT,99998) 'Optimum workspace required = ', LWKOPT,
     +        'Workspace provided         = ', LWORK
         END IF
      ELSE
         WRITE (NOUT,*)
         WRITE (NOUT,*) 'NMAX too small'
      END IF
      STOP
*
99999 FORMAT (1X,A,I4)
99998 FORMAT (1X,A,I5,/1X,A,I5)
      END