org.netlib.lapack
Class DGEEV

java.lang.Object
  org.netlib.lapack.DGEEV

public class DGEEV
extends java.lang.Object

DGEEV is a simplified interface to the JLAPACK routine dgeev.
This interface converts Java-style 2D row-major arrays into
the 1D column-major linearized arrays expected by the lower
level JLAPACK routines.  Using this interface also allows you
to omit offset and leading dimension arguments.  However, because
of these conversions, these routines will be slower than the low
level ones.  Following is the description from the original Fortran
source.  Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *  Purpose
 *  =======
 *
 *  DGEEV computes for an N-by-N real 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.
 *
 *  Arguments
 *  =========
 *
 *  JOBVL   (input) CHARACTER*1
 *          = 'N': left eigenvectors of A are not computed;
 *          = 'V': left eigenvectors of A are computed.
 *
 *  JOBVR   (input) CHARACTER*1
 *          = 'N': right eigenvectors of A are not computed;
 *          = 'V': right eigenvectors of A are computed.
 *
 *  N       (input) INTEGER
 *          The order of the matrix A. N >= 0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the N-by-N matrix A.
 *          On exit, A has been overwritten.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= max(1,N).
 *
 *  WR      (output) DOUBLE PRECISION array, dimension (N)
 *  WI      (output) DOUBLE PRECISION array, dimension (N)
 *          WR and WI contain the real and imaginary parts,
 *          respectively, of the computed eigenvalues.  Complex
 *          conjugate pairs of eigenvalues appear consecutively
 *          with the eigenvalue having the positive imaginary part
 *          first.
 *
 *  VL      (output) DOUBLE PRECISION 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.
 *          If the j-th eigenvalue is real, then u(j) = VL(:,j),
 *          the j-th column of VL.
 *          If the j-th and (j+1)-st eigenvalues form a complex
 *          conjugate pair, then u(j) = VL(:,j) + i*VL(:,j+1) and
 *          u(j+1) = VL(:,j) - i*VL(:,j+1).
 *
 *  LDVL    (input) INTEGER
 *          The leading dimension of the array VL.  LDVL >= 1; if
 *          JOBVL = 'V', LDVL >= N.
 *
 *  VR      (output) DOUBLE PRECISION 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.
 *          If the j-th eigenvalue is real, then v(j) = VR(:,j),
 *          the j-th column of VR.
 *          If the j-th and (j+1)-st eigenvalues form a complex
 *          conjugate pair, then v(j) = VR(:,j) + i*VR(:,j+1) and
 *          v(j+1) = VR(:,j) - i*VR(:,j+1).
 *
 *  LDVR    (input) INTEGER
 *          The leading dimension of the array VR.  LDVR >= 1; if
 *          JOBVR = 'V', LDVR >= N.
 *
 *  WORK    (workspace/output) DOUBLE PRECISION array, dimension (LWORK)

 *          On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
 *
 *  LWORK   (input) INTEGER
 *          The dimension of the array WORK.  LWORK >= max(1,3*N), and
 *          if JOBVL = 'V' or JOBVR = 'V', LWORK >= 4*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.
 *
 *  INFO    (output) 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 i+1:N of WR and WI contain eigenvalues which
 *                have converged.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Constructor Summary

DGEEV()

Method Summary

static void

DGEEV(java.lang.String jobvl, java.lang.String jobvr, int n, double[][] a, double[] wr, double[] wi, double[][] vl, double[][] vr, double[] work, int lwork, intW info)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DGEEV

public DGEEV()

Method Detail

DGEEV

public static void DGEEV(java.lang.String jobvl,
                         java.lang.String jobvr,
                         int n,
                         double[][] a,
                         double[] wr,
                         double[] wi,
                         double[][] vl,
                         double[][] vr,
                         double[] work,
                         int lwork,
                         intW info)