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Class org.netlib.lapack.DSTEV

java.lang.Object
   |
   +----org.netlib.lapack.DSTEV

public class DSTEV

extends Object

DSTEV is a simplified interface to the JLAPACK routine dstev.
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
 *  =======
 *
 *  DSTEV computes all eigenvalues and, optionally, eigenvectors of a
 *  real symmetric tridiagonal matrix A.
 *
 *  Arguments
 *  =========
 *
 *  JOBZ    (input) CHARACTER*1
 *          = 'N':  Compute eigenvalues only;
 *          = 'V':  Compute eigenvalues and eigenvectors.
 *
 *  N       (input) INTEGER
 *          The order of the matrix.  N >= 0.
 *
 *  D       (input/output) DOUBLE PRECISION array, dimension (N)
 *          On entry, the n diagonal elements of the tridiagonal matrix
 *          A.
 *          On exit, if INFO = 0, the eigenvalues in ascending order.
 *
 *  E       (input/output) DOUBLE PRECISION array, dimension (N)
 *          On entry, the (n-1) subdiagonal elements of the tridiagonal
 *          matrix A, stored in elements 1 to N-1 of E; E(N) need not
 *          be set, but is used by the routine.
 *          On exit, the contents of E are destroyed.
 *
 *  Z       (output) DOUBLE PRECISION array, dimension (LDZ, N)
 *          If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal
 *          eigenvectors of the matrix A, with the i-th column of Z
 *          holding the eigenvector associated with D(i).
 *          If JOBZ = 'N', then Z is not referenced.
 *
 *  LDZ     (input) INTEGER
 *          The leading dimension of the array Z.  LDZ >= 1, and if
 *          JOBZ = 'V', LDZ >= max(1,N).
 *
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (max(1,2*N-2))
 *          If JOBZ = 'N', WORK is not referenced.
 *
 *  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 E did not converge to zero.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DSTEV()

DSTEV(String, int, double[], double[], double[][], double[], intW)

 public DSTEV()

 public static void DSTEV(String jobz,
                          int n,
                          double d[],
                          double e[],
                          double z[][],
                          double work[],
                          intW info)

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