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## org.netlib.lapack
Class SSPEVD

    java.lang.Object
      org.netlib.lapack.SSPEVD

    public class SSPEVD

extends java.lang.Object

    SSPEVD is a simplified interface to the JLAPACK routine sspevd.
    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
     *  =======
     *
     *  SSPEVD computes all the eigenvalues and, optionally, eigenvectors
     *  of a real symmetric matrix A in packed storage. 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.
     *
     *  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.
     *
     *  AP      (input/output) REAL array, dimension (N*(N+1)/2)
     *          On entry, the upper or lower triangle of the symmetric matrix
     *          A, packed columnwise in a linear array.  The j-th column of A
     *          is stored in the array AP as follows:
     *          if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
     *          if UPLO = 'L', AP(i + (j-1)*(2*n-j)/2) = A(i,j) for j<=i<=n.

     *
     *          On exit, AP is overwritten by values generated during the
     *          reduction to tridiagonal form.  If UPLO = 'U', the diagonal
     *          and first superdiagonal of the tridiagonal matrix T overwrite
     *          the corresponding elements of A, and if UPLO = 'L', the
     *          diagonal and first subdiagonal of T overwrite the
     *          corresponding elements of A.
     *
     *  W       (output) REAL array, dimension (N)
     *          If INFO = 0, the eigenvalues in ascending order.
     *
     *  Z       (output) REAL 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/output) REAL array, dimension (MAX(1,LWORK))
     *          On exit, if INFO = 0, WORK(1) returns the required 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.
     *          If JOBZ = 'V' and N > 1, LWORK must be at least
     *                                                 1 + 6*N + N**2.
     *
     *          If LWORK = -1, then a workspace query is assumed; the routine
     *          only calculates the required 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 required LIWORK.
     *
     *  LIWORK  (input) INTEGER
     *          The dimension of the array IWORK.
     *          If JOBZ  = 'N' or 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 required 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, the algorithm failed to converge; i
     *                off-diagonal elements of an intermediate tridiagonal
     *                form did not converge to zero.
     *
     *  =====================================================================
     *
     *     .. Parameters ..

Constructor Summary
`SSPEVD()`

Method Summary
`static void` | `SSPEVD(java.lang.String jobz, java.lang.String uplo, int n, float[] ap, float[] w, float[][] z, float[] work, int lwork, int[] iwork, int liwork, intW info)`

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

Constructor Detail

### SSPEVD

    public SSPEVD()

Method Detail

### SSPEVD

    public static void SSPEVD(java.lang.String jobz,
                              java.lang.String uplo,
                              int n,
                              float[] ap,
                              float[] w,
                              float[][] z,
                              float[] work,
                              int lwork,
                              int[] iwork,
                              int liwork,
                              intW info)

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