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## org.netlib.lapack
Class SLARRF

    java.lang.Object
      org.netlib.lapack.SLARRF

    public class SLARRF

extends java.lang.Object

    SLARRF is a simplified interface to the JLAPACK routine slarrf.
    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
     *  =======
     *
     *  Given the initial representation L D L^T and its cluster of close
     *  eigenvalues (in a relative measure), W( CLSTRT ), W( CLSTRT+1 ), ...

     *  W( CLEND ), SLARRF finds a new relatively robust representation
     *  L D L^T - SIGMA I = L(+) D(+) L(+)^T such that at least one of the
     *  eigenvalues of L(+) D(+) L(+)^T is relatively isolated.
     *
     *  Arguments
     *  =========
     *
     *  N       (input) INTEGER
     *          The order of the matrix (subblock, if the matrix splitted).
     *
     *  D       (input) REAL             array, dimension (N)
     *          The N diagonal elements of the diagonal matrix D.
     *
     *  L       (input) REAL             array, dimension (N-1)
     *          The (N-1) subdiagonal elements of the unit bidiagonal
     *          matrix L.
     *
     *  LD      (input) REAL             array, dimension (N-1)
     *          The (N-1) elements L(i)*D(i).
     *
     *  CLSTRT  (input) INTEGER
     *          The index of the first eigenvalue in the cluster.
     *
     *  CLEND   (input) INTEGER
     *          The index of the last eigenvalue in the cluster.
     *
     *  W       (input) REAL             array, dimension >=  (CLEND-CLSTRT+1
     *          The eigenvalue APPROXIMATIONS of L D L^T in ascending order.

     *          W( CLSTRT ) through W( CLEND ) form the cluster of relatively
     *          close eigenalues.
     *
     *  WGAP    (input/output) REAL             array, dimension >=  (CLEND-C
     *          The separation from the right neighbor eigenvalue in W.
     *
     *  WERR    (input) REAL             array, dimension >=  (CLEND-CLSTRT+1
     *          WERR contain the semiwidth of the uncertainty
     *          interval of the corresponding eigenvalue APPROXIMATION in W
     *
     *  SPDIAM (input) estimate of the spectral diameter obtained from the
     *          Gerschgorin intervals
     *
     *  CLGAPL, CLGAPR (input) absolute gap on each end of the cluster.
     *          Set by the calling routine to protect against shifts too clos
     *          to eigenvalues outside the cluster.
     *
     *  PIVMIN  (input) DOUBLE PRECISION
     *          The minimum pivot allowed in the Sturm sequence.
     *
     *  SIGMA   (output) REAL
     *          The shift used to form L(+) D(+) L(+)^T.
     *
     *  DPLUS   (output) REAL             array, dimension (N)
     *          The N diagonal elements of the diagonal matrix D(+).
     *
     *  LPLUS   (output) REAL             array, dimension (N-1)
     *          The first (N-1) elements of LPLUS contain the subdiagonal
     *          elements of the unit bidiagonal matrix L(+).
     *
     *  WORK    (workspace) REAL             array, dimension (2*N)
     *          Workspace.
     *
     *  Further Details
     *  ===============
     *
     *  Based on contributions by
     *     Beresford Parlett, University of California, Berkeley, USA
     *     Jim Demmel, University of California, Berkeley, USA
     *     Inderjit Dhillon, University of Texas, Austin, USA
     *     Osni Marques, LBNL/NERSC, USA
     *     Christof Voemel, University of California, Berkeley, USA
     *
     *  =====================================================================
     *
     *     .. Parameters ..

Constructor Summary
`SLARRF()`

Method Summary
`static void` | `SLARRF(int n, float[] d, float[] l, float[] ld, int clstrt, int clend, float[] w, float[] wgap, float[] werr, float spdiam, float clgapl, float clgapr, float pivmin, floatW sigma, float[] dplus, float[] lplus, float[] work, intW info)`

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

Constructor Detail

### SLARRF

    public SLARRF()

Method Detail

### SLARRF

    public static void SLARRF(int n,
                              float[] d,
                              float[] l,
                              float[] ld,
                              int clstrt,
                              int clend,
                              float[] w,
                              float[] wgap,
                              float[] werr,
                              float spdiam,
                              float clgapl,
                              float clgapr,
                              float pivmin,
                              floatW sigma,
                              float[] dplus,
                              float[] lplus,
                              float[] work,
                              intW info)

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