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cgeev.f(3)                          LAPACK                          cgeev.f(3)

NAME
       cgeev.f -

SYNOPSIS
   Functions/Subroutines
       subroutine cgeev (JOBVL, JOBVR, N, A, LDA, W, VL, LDVL, VR, LDVR, WORK,
           LWORK, RWORK, INFO)
            CGEEV computes the eigenvalues and, optionally, the left and/or
           right eigenvectors for GE matrices

Function/Subroutine Documentation
   subroutine cgeev (characterJOBVL, characterJOBVR, integerN, complex,
       dimension( lda, * )A, integerLDA, complex, dimension( * )W, complex,
       dimension( ldvl, * )VL, integerLDVL, complex, dimension( ldvr, * )VR,
       integerLDVR, complex, dimension( * )WORK, integerLWORK, real,
       dimension( * )RWORK, integerINFO)
        CGEEV computes the eigenvalues and, optionally, the left and/or right
       eigenvectors for GE matrices

       Purpose:

            CGEEV computes for an N-by-N complex nonsymmetric matrix A, the
            eigenvalues and, optionally, the left and/or right eigenvectors.

            The right eigenvector v(j) of A satisfies
                             A * v(j) = lambda(j) * v(j)
            where lambda(j) is its eigenvalue.
            The left eigenvector u(j) of A satisfies
                          u(j)**H * A = lambda(j) * u(j)**H
            where u(j)**H denotes the conjugate transpose of u(j).

            The computed eigenvectors are normalized to have Euclidean norm
            equal to 1 and largest component real.

       Parameters:
           JOBVL

                     JOBVL is CHARACTER*1
                     = 'N': left eigenvectors of A are not computed;
                     = 'V': left eigenvectors of are computed.

           JOBVR

                     JOBVR is CHARACTER*1
                     = 'N': right eigenvectors of A are not computed;
                     = 'V': right eigenvectors of A are computed.

           N

                     N is INTEGER
                     The order of the matrix A. N >= 0.

           A

                     A is COMPLEX array, dimension (LDA,N)
                     On entry, the N-by-N matrix A.
                     On exit, A has been overwritten.

           LDA

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

           W

                     W is COMPLEX array, dimension (N)
                     W contains the computed eigenvalues.

           VL

                     VL is COMPLEX array, dimension (LDVL,N)
                     If JOBVL = 'V', the left eigenvectors u(j) are stored one
                     after another in the columns of VL, in the same order
                     as their eigenvalues.
                     If JOBVL = 'N', VL is not referenced.
                     u(j) = VL(:,j), the j-th column of VL.

           LDVL

                     LDVL is INTEGER
                     The leading dimension of the array VL.  LDVL >= 1; if
                     JOBVL = 'V', LDVL >= N.

           VR

                     VR is COMPLEX array, dimension (LDVR,N)
                     If JOBVR = 'V', the right eigenvectors v(j) are stored one
                     after another in the columns of VR, in the same order
                     as their eigenvalues.
                     If JOBVR = 'N', VR is not referenced.
                     v(j) = VR(:,j), the j-th column of VR.

           LDVR

                     LDVR is INTEGER
                     The leading dimension of the array VR.  LDVR >= 1; if
                     JOBVR = 'V', LDVR >= N.

           WORK

                     WORK is COMPLEX 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.

                     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 REAL array, dimension (2*N)

           INFO

                     INFO is INTEGER
                     = 0:  successful exit
                     < 0:  if INFO = -i, the i-th argument had an illegal value.
                     > 0:  if INFO = i, the QR algorithm failed to compute all the
                           eigenvalues, and no eigenvectors have been computed;
                           elements and i+1:N of W contain eigenvalues which have
                           converged.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           November 2011

       Definition at line 177 of file cgeev.f.

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

Version 3.4.2                   Sat Nov 16 2013                     cgeev.f(3)