org.netlib.lapack
Class DSYEV

java.lang.Object
  org.netlib.lapack.DSYEV

public class DSYEV
extends java.lang.Object

DSYEV is a simplified interface to the JLAPACK routine dsyev.
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
 *  =======
 *
 *  DSYEV computes all eigenvalues and, optionally, eigenvectors of a
 *  real symmetric matrix A.
 *
 *  Arguments
 *  =========
 *
 *  JOBZ    (input) CHARACTER*1
 *          = 'N':  Compute eigenvalues only;
 *          = 'V':  Compute eigenvalues and eigenvectors.
 *
 *  UPLO    (input) CHARACTER*1
 *          = 'U':  Upper triangle of A is stored;
 *          = 'L':  Lower triangle of A is stored.
 *
 *  N       (input) INTEGER
 *          The order of the matrix A.  N >= 0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA, N)
 *          On entry, the symmetric matrix A.  If UPLO = 'U', the
 *          leading N-by-N upper triangular part of A contains the
 *          upper triangular part of the matrix A.  If UPLO = 'L',
 *          the leading N-by-N lower triangular part of A contains
 *          the lower triangular part of the matrix A.
 *          On exit, if JOBZ = 'V', then if INFO = 0, A contains the
 *          orthonormal eigenvectors of the matrix A.
 *          If JOBZ = 'N', then on exit the lower triangle (if UPLO='L')

 *          or the upper triangle (if UPLO='U') of A, including the
 *          diagonal, is destroyed.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= max(1,N).
 *
 *  W       (output) DOUBLE PRECISION array, dimension (N)
 *          If INFO = 0, the eigenvalues in ascending order.
 *
 *  WORK    (workspace/output) DOUBLE PRECISION array, dimension (LWORK)

 *          On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
 *
 *  LWORK   (input) INTEGER
 *          The length of the array WORK.  LWORK >= max(1,3*N-1).
 *          For optimal efficiency, LWORK >= (NB+2)*N,
 *          where NB is the blocksize for DSYTRD returned by ILAENV.
 *
 *          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 algorithm failed to converge; i
 *                off-diagonal elements of an intermediate tridiagonal
 *                form did not converge to zero.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Constructor Summary

DSYEV()

Method Summary

static void

DSYEV(java.lang.String jobz, java.lang.String uplo, int n, double[][] a, double[] w, 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

DSYEV

public DSYEV()

Method Detail

DSYEV

public static void DSYEV(java.lang.String jobz,
                         java.lang.String uplo,
                         int n,
                         double[][] a,
                         double[] w,
                         double[] work,
                         int lwork,
                         intW info)