org.netlib.lapack
Class Slasd5

java.lang.Object
  extended by org.netlib.lapack.Slasd5

public class Slasd5
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 * ======= * * This subroutine computes the square root of the I-th eigenvalue * of a positive symmetric rank-one modification of a 2-by-2 diagonal * matrix * * diag( D ) * diag( D ) + RHO * Z * transpose(Z) . * * The diagonal entries in the array D are assumed to satisfy * * 0 <= 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) REAL array, dimension ( 2 ) * The original eigenvalues. We assume 0 <= D(1) < D(2). * * Z (input) REAL array, dimension ( 2 ) * The components of the updating vector. * * DELTA (output) REAL array, dimension ( 2 ) * Contains (D(j) - lambda_I) in its j-th component. * The vector DELTA contains the information necessary * to construct the eigenvectors. * * RHO (input) REAL * The scalar in the symmetric updating formula. * * DSIGMA (output) REAL * The computed lambda_I, the I-th updated eigenvalue. * * WORK (workspace) REAL array, dimension ( 2 ) * WORK contains (D(j) + sigma_I) in its j-th component. * * Further Details * =============== * * Based on contributions by * Ren-Cang Li, Computer Science Division, University of California * at Berkeley, USA * * ===================================================================== * * .. Parameters ..


Constructor Summary
Slasd5()
           
 
Method Summary
static void slasd5(int i, float[] d, int _d_offset, float[] z, int _z_offset, float[] delta, int _delta_offset, float rho, floatW dsigma, float[] work, int _work_offset)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Slasd5

public Slasd5()
Method Detail

slasd5

public static void slasd5(int i,
                          float[] d,
                          int _d_offset,
                          float[] z,
                          int _z_offset,
                          float[] delta,
                          int _delta_offset,
                          float rho,
                          floatW dsigma,
                          float[] work,
                          int _work_offset)