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## org.netlib.lapack
Class Dlaqr1

    java.lang.Object
      org.netlib.lapack.Dlaqr1

    public class Dlaqr1

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.

     *     ..
     *
     *       Given a 2-by-2 or 3-by-3 matrix H, DLAQR1 sets v to a
     *       scalar multiple of the first column of the product
     *
     *       (*)  K = (H - (sr1 + i*si1)*I)*(H - (sr2 + i*si2)*I)
     *
     *       scaling to avoid overflows and most underflows. It
     *       is assumed that either
     *
     *               1) sr1 = sr2 and si1 = -si2
     *           or
     *               2) si1 = si2 = 0.
     *
     *       This is useful for starting double implicit shift bulges
     *       in the QR algorithm.
     *
     *
     *       N      (input) integer
     *              Order of the matrix H. N must be either 2 or 3.
     *
     *       H      (input) DOUBLE PRECISION array of dimension (LDH,N)
     *              The 2-by-2 or 3-by-3 matrix H in (*).
     *
     *       LDH    (input) integer
     *              The leading dimension of H as declared in
     *              the calling procedure.  LDH.GE.N
     *
     *       SR1    (input) DOUBLE PRECISION
     *       SI1    The shifts in (*).
     *       SR2
     *       SI2
     *
     *       V      (output) DOUBLE PRECISION array of dimension N
     *              A scalar multiple of the first column of the
     *              matrix K in (*).
     *
     *     ================================================================
     *     Based on contributions by
     *        Karen Braman and Ralph Byers, Department of Mathematics,
     *        University of Kansas, USA
     *
     *     ================================================================
     *
     *     .. Parameters ..

Constructor Summary
`Dlaqr1()`

Method Summary
`static void` | `dlaqr1(int n, double[] h, int _h_offset, int ldh, double sr1, double si1, double sr2, double si2, double[] v, int _v_offset)`

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

Constructor Detail

### Dlaqr1

    public Dlaqr1()

Method Detail

### dlaqr1

    public static void dlaqr1(int n,
                              double[] h,
                              int _h_offset,
                              int ldh,
                              double sr1,
                              double si1,
                              double sr2,
                              double si2,
                              double[] v,
                              int _v_offset)

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