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## org.netlib.lapack
Class Dlaic1

    java.lang.Object
      org.netlib.lapack.Dlaic1

    public class Dlaic1

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
     *  =======
     *
     *  DLAIC1 applies one step of incremental condition estimation in
     *  its simplest version:
     *
     *  Let x, twonorm(x) = 1, be an approximate singular vector of an j-by-j
     *  lower triangular matrix L, such that
     *           twonorm(L*x) = sest
     *  Then DLAIC1 computes sestpr, s, c such that
     *  the vector
     *                  [ s*x ]
     *           xhat = [  c  ]
     *  is an approximate singular vector of
     *                  [ L     0  ]
     *           Lhat = [ w' gamma ]
     *  in the sense that
     *           twonorm(Lhat*xhat) = sestpr.
     *
     *  Depending on JOB, an estimate for the largest or smallest singular
     *  value is computed.
     *
     *  Note that [s c]' and sestpr**2 is an eigenpair of the system
     *
     *      diag(sest*sest, 0) + [alpha  gamma] * [ alpha ]
     *                                            [ gamma ]
     *
     *  where  alpha =  x'*w.
     *
     *  Arguments
     *  =========
     *
     *  JOB     (input) INTEGER
     *          = 1: an estimate for the largest singular value is computed.

     *          = 2: an estimate for the smallest singular value is computed.
     *
     *  J       (input) INTEGER
     *          Length of X and W
     *
     *  X       (input) DOUBLE PRECISION array, dimension (J)
     *          The j-vector x.
     *
     *  SEST    (input) DOUBLE PRECISION
     *          Estimated singular value of j by j matrix L
     *
     *  W       (input) DOUBLE PRECISION array, dimension (J)
     *          The j-vector w.
     *
     *  GAMMA   (input) DOUBLE PRECISION
     *          The diagonal element gamma.
     *
     *  SESTPR  (output) DOUBLE PRECISION
     *          Estimated singular value of (j+1) by (j+1) matrix Lhat.
     *
     *  S       (output) DOUBLE PRECISION
     *          Sine needed in forming xhat.
     *
     *  C       (output) DOUBLE PRECISION
     *          Cosine needed in forming xhat.
     *
     *  =====================================================================
     *
     *     .. Parameters ..

Constructor Summary
`Dlaic1()`

Method Summary
`static void` | `dlaic1(int job, int j, double[] x, int _x_offset, double sest, double[] w, int _w_offset, double gamma, doubleW sestpr, doubleW s, doubleW c)`

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

Constructor Detail

### Dlaic1

    public Dlaic1()

Method Detail

### dlaic1

    public static void dlaic1(int job,
                              int j,
                              double[] x,
                              int _x_offset,
                              double sest,
                              double[] w,
                              int _w_offset,
                              double gamma,
                              doubleW sestpr,
                              doubleW s,
                              doubleW c)

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