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Class org.netlib.lapack.DLAED5

java.lang.Object
   |
   +----org.netlib.lapack.DLAED5

public class DLAED5

extends Object

DLAED5 is a simplified interface to the JLAPACK routine dlaed5.
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
 *  =======
 *
 *  This subroutine computes the I-th eigenvalue of a symmetric rank-one
 *  modification of a 2-by-2 diagonal matrix
 *
 *             diag( D )  +  RHO *  Z * transpose(Z) .
 *
 *  The diagonal elements in the array D are assumed to satisfy
 *
 *             D(i) < D(j)  for  i < j .
 *
 *  We also assume RHO > 0 and that the Euclidean norm of the vector
 *  Z is one.
 *
 *  Arguments
 *  =========
 *
 *  I      (input) INTEGER
 *         The index of the eigenvalue to be computed.  I = 1 or I = 2.
 *
 *  D      (input) DOUBLE PRECISION array, dimension (2)
 *         The original eigenvalues.  We assume D(1) < D(2).
 *
 *  Z      (input) DOUBLE PRECISION array, dimension (2)
 *         The components of the updating vector.
 *
 *  DELTA  (output) DOUBLE PRECISION array, dimension (2)
 *         The vector DELTA contains the information necessary
 *         to construct the eigenvectors.
 *
 *  RHO    (input) DOUBLE PRECISION
 *         The scalar in the symmetric updating formula.
 *
 *  DLAM   (output) DOUBLE PRECISION
 *         The computed lambda_I, the I-th updated eigenvalue.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DLAED5()

DLAED5(int, double[], double[], double[], double, doubleW)

 public DLAED5()

 public static void DLAED5(int i,
                           double d[],
                           double z[],
                           double delta[],
                           double rho,
                           doubleW dlam)

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