org.netlib.lapack
Class Slaic1

java.lang.Object
  extended by org.netlib.lapack.Slaic1

public class Slaic1
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 * ======= * * SLAIC1 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 SLAIC1 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) REAL array, dimension (J) * The j-vector x. * * SEST (input) REAL * Estimated singular value of j by j matrix L * * W (input) REAL array, dimension (J) * The j-vector w. * * GAMMA (input) REAL * The diagonal element gamma. * * SESTPR (output) REAL * Estimated singular value of (j+1) by (j+1) matrix Lhat. * * S (output) REAL * Sine needed in forming xhat. * * C (output) REAL * Cosine needed in forming xhat. * * ===================================================================== * * .. Parameters ..


Constructor Summary
Slaic1()
           
 
Method Summary
static void slaic1(int job, int j, float[] x, int _x_offset, float sest, float[] w, int _w_offset, float gamma, floatW sestpr, floatW s, floatW c)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Slaic1

public Slaic1()
Method Detail

slaic1

public static void slaic1(int job,
                          int j,
                          float[] x,
                          int _x_offset,
                          float sest,
                          float[] w,
                          int _w_offset,
                          float gamma,
                          floatW sestpr,
                          floatW s,
                          floatW c)