Provided by: liblapack-doc_3.3.1-1_all bug

NAME

       LAPACK-3 - uses inverse iteration to find a right or left eigenvector corresponding to the
       eigenvalue W of a complex upper Hessenberg matrix H

SYNOPSIS

       SUBROUTINE CLAEIN( RIGHTV, NOINIT, N, H, LDH, W, V, B, LDB, RWORK, EPS3, SMLNUM, INFO )

           LOGICAL        NOINIT, RIGHTV

           INTEGER        INFO, LDB, LDH, N

           REAL           EPS3, SMLNUM

           COMPLEX        W

           REAL           RWORK( * )

           COMPLEX        B( LDB, * ), H( LDH, * ), V( * )

PURPOSE

       CLAEIN uses inverse iteration to find a right or left  eigenvector  corresponding  to  the
       eigenvalue W of a complex upper Hessenberg matrix H.

ARGUMENTS

        RIGHTV   (input) LOGICAL
                 = .TRUE. : compute right eigenvector;
                 = .FALSE.: compute left eigenvector.

        NOINIT   (input) LOGICAL
                 = .TRUE. : no initial vector supplied in V
                 = .FALSE.: initial vector supplied in V.

        N       (input) INTEGER
                The order of the matrix H.  N >= 0.

        H       (input) COMPLEX array, dimension (LDH,N)
                The upper Hessenberg matrix H.

        LDH     (input) INTEGER
                The leading dimension of the array H.  LDH >= max(1,N).

        W       (input) COMPLEX
                The eigenvalue of H whose corresponding right or left
                eigenvector is to be computed.

        V       (input/output) COMPLEX array, dimension (N)
                On entry, if NOINIT = .FALSE., V must contain a starting
                vector for inverse iteration; otherwise V need not be set.
                On exit, V contains the computed eigenvector, normalized so
                that the component of largest magnitude has magnitude 1; here
                the magnitude of a complex number (x,y) is taken to be
                |x| + |y|.

        B       (workspace) COMPLEX array, dimension (LDB,N)

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

        RWORK   (workspace) REAL array, dimension (N)

        EPS3    (input) REAL
                A small machine-dependent value which is used to perturb
                close eigenvalues, and to replace zero pivots.

        SMLNUM  (input) REAL
                A machine-dependent value close to the underflow threshold.

        INFO    (output) INTEGER
                = 0:  successful exit
                = 1:  inverse iteration did not converge; V is set to the
                last iterate.

 LAPACK auxiliary routine (version 3.3.1)   April 2011                            CLAEIN(3lapack)