org.netlib.lapack
Class Slaed4

java.lang.Object
  extended by org.netlib.lapack.Slaed4

public class Slaed4
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 I-th updated eigenvalue of a symmetric * rank-one modification to a diagonal matrix whose elements are * given in the array d, and that * * D(i) < D(j) for i < j * * and that RHO > 0. This is arranged by the calling routine, and is * no loss in generality. The rank-one modified system is thus * * diag( D ) + RHO * Z * Z_transpose. * * where we assume the Euclidean norm of Z is 1. * * The method consists of approximating the rational functions in the * secular equation by simpler interpolating rational functions. * * Arguments * ========= * * N (input) INTEGER * The length of all arrays. * * I (input) INTEGER * The index of the eigenvalue to be computed. 1 <= I <= N. * * D (input) REAL array, dimension (N) * The original eigenvalues. It is assumed that they are in * order, D(I) < D(J) for I < J. * * Z (input) REAL array, dimension (N) * The components of the updating vector. * * DELTA (output) REAL array, dimension (N) * If N .ne. 1, DELTA contains (D(j) - lambda_I) in its j-th * component. If N = 1, then DELTA(1) = 1. The vector DELTA * contains the information necessary to construct the * eigenvectors. * * RHO (input) REAL * The scalar in the symmetric updating formula. * * DLAM (output) REAL * The computed lambda_I, the I-th updated eigenvalue. * * INFO (output) INTEGER * = 0: successful exit * > 0: if INFO = 1, the updating process failed. * * Internal Parameters * =================== * * Logical variable ORGATI (origin-at-i?) is used for distinguishing * whether D(i) or D(i+1) is treated as the origin. * * ORGATI = .true. origin at i * ORGATI = .false. origin at i+1 * * Logical variable SWTCH3 (switch-for-3-poles?) is for noting * if we are working with THREE poles! * * MAXIT is the maximum number of iterations allowed for each * eigenvalue. * * Further Details * =============== * * Based on contributions by * Ren-Cang Li, Computer Science Division, University of California * at Berkeley, USA * * ===================================================================== * * .. Parameters ..


Constructor Summary
Slaed4()
           
 
Method Summary
static void slaed4(int n, int i, float[] d, int _d_offset, float[] z, int _z_offset, float[] delta, int _delta_offset, float rho, floatW dlam, intW info)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Slaed4

public Slaed4()
Method Detail

slaed4

public static void slaed4(int n,
                          int i,
                          float[] d,
                          int _d_offset,
                          float[] z,
                          int _z_offset,
                          float[] delta,
                          int _delta_offset,
                          float rho,
                          floatW dlam,
                          intW info)