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## org.netlib.lapack
Class Ssyevd

    java.lang.Object
      org.netlib.lapack.Ssyevd

    public class Ssyevd

extends java.lang.Object

    Following is the description from the original
    Fortran source.  For each array argument, the Java
    version will include an integer offset parameter, so
    the arguments may not match the description exactly.
    Contact seymour@cs.utk.edu with any questions.

     *     ..
     *
     *  Purpose
     *  =======
     *
     *  SSYEVD computes all eigenvalues and, optionally, eigenvectors of a
     *  real symmetric matrix A. If eigenvectors are desired, it uses a
     *  divide and conquer algorithm.
     *
     *  The divide and conquer algorithm makes very mild assumptions about
     *  floating point arithmetic. It will work on machines with a guard
     *  digit in add/subtract, or on those binary machines without guard
     *  digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
     *  Cray-2. It could conceivably fail on hexadecimal or decimal machines

     *  without guard digits, but we know of none.
     *
     *  Because of large use of BLAS of level 3, SSYEVD needs N**2 more
     *  workspace than SSYEVX.
     *
     *  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) REAL 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) REAL array, dimension (N)
     *          If INFO = 0, the eigenvalues in ascending order.
     *
     *  WORK    (workspace/output) REAL array,
     *                                         dimension (LWORK)
     *          On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
     *
     *  LWORK   (input) INTEGER
     *          The dimension of the array WORK.
     *          If N <= 1,               LWORK must be at least 1.
     *          If JOBZ = 'N' and N > 1, LWORK must be at least 2*N+1.
     *          If JOBZ = 'V' and N > 1, LWORK must be at least
     *                                                1 + 6*N + 2*N**2.
     *
     *          If LWORK = -1, then a workspace query is assumed; the routine
     *          only calculates the optimal sizes of the WORK and IWORK
     *          arrays, returns these values as the first entries of the WORK
     *          and IWORK arrays, and no error message related to LWORK or
     *          LIWORK is issued by XERBLA.
     *
     *  IWORK   (workspace/output) INTEGER array, dimension (MAX(1,LIWORK))
     *          On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK.
     *
     *  LIWORK  (input) INTEGER
     *          The dimension of the array IWORK.
     *          If N <= 1,                LIWORK must be at least 1.
     *          If JOBZ  = 'N' and N > 1, LIWORK must be at least 1.
     *          If JOBZ  = 'V' and N > 1, LIWORK must be at least 3 + 5*N.
     *
     *          If LIWORK = -1, then a workspace query is assumed; the
     *          routine only calculates the optimal sizes of the WORK and
     *          IWORK arrays, returns these values as the first entries of
     *          the WORK and IWORK arrays, and no error message related to
     *          LWORK or LIWORK 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 and JOBZ = 'N', then the algorithm failed
     *                to converge; i off-diagonal elements of an intermediate
     *                tridiagonal form did not converge to zero;
     *                if INFO = i and JOBZ = 'V', then the algorithm failed
     *                to compute an eigenvalue while working on the submatrix
     *                lying in rows and columns INFO/(N+1) through
     *                mod(INFO,N+1).
     *
     *  Further Details
     *  ===============
     *
     *  Based on contributions by
     *     Jeff Rutter, Computer Science Division, University of California
     *     at Berkeley, USA
     *  Modified by Francoise Tisseur, University of Tennessee.
     *
     *  Modified description of INFO. Sven, 16 Feb 05.
     *  =====================================================================
     *
     *     .. Parameters ..

Constructor Summary
`Ssyevd()`

Method Summary
`static void` | `ssyevd(java.lang.String jobz, java.lang.String uplo, int n, float[] a, int _a_offset, int lda, float[] w, int _w_offset, float[] work, int _work_offset, int lwork, int[] iwork, int _iwork_offset, int liwork, intW info)`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### Ssyevd

    public Ssyevd()

Method Detail

### ssyevd

    public static void ssyevd(java.lang.String jobz,
                              java.lang.String uplo,
                              int n,
                              float[] a,
                              int _a_offset,
                              int lda,
                              float[] w,
                              int _w_offset,
                              float[] work,
                              int _work_offset,
                              int lwork,
                              int[] iwork,
                              int _iwork_offset,
                              int liwork,
                              intW info)

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