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Class org.netlib.lapack.DSBEV

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

public class DSBEV

extends Object

DSBEV is a simplified interface to the JLAPACK routine dsbev.
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
 *  =======
 *
 *  DSBEV computes all the eigenvalues and, optionally, eigenvectors of
 *  a real symmetric band 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.
 *
 *  KD      (input) INTEGER
 *          The number of superdiagonals of the matrix A if UPLO = 'U',
 *          or the number of subdiagonals if UPLO = 'L'.  KD >= 0.
 *
 *  AB      (input/output) DOUBLE PRECISION array, dimension (LDAB, N)
 *          On entry, the upper or lower triangle of the symmetric band
 *          matrix A, stored in the first KD+1 rows of the array.  The
 *          j-th column of A is stored in the j-th column of the array AB
 *          as follows:
 *          if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-kd)<=i<=j;
 *          if UPLO = 'L', AB(1+i-j,j)    = A(i,j) for j<=i<=min(n,j+kd).
 *
 *          On exit, AB is overwritten by values generated during the
 *          reduction to tridiagonal form.  If UPLO = 'U', the first
 *          superdiagonal and the diagonal of the tridiagonal matrix T
 *          are returned in rows KD and KD+1 of AB, and if UPLO = 'L',
 *          the diagonal and first subdiagonal of T are returned in the
 *          first two rows of AB.
 *
 *  LDAB    (input) INTEGER
 *          The leading dimension of the array AB.  LDAB >= KD + 1.
 *
 *  W       (output) DOUBLE PRECISION array, dimension (N)
 *          If INFO = 0, the eigenvalues in ascending order.
 *
 *  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 W(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(1,3*N-2))
 *
 *  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 ..

DSBEV()

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

 public DSBEV()

 public static void DSBEV(String jobz,
                          String uplo,
                          int n,
                          int kd,
                          double ab[][],
                          double w[],
                          double z[][],
                          double work[],
                          intW info)

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