Unix/Linux Go Back    


RedHat 9 (Linux i386) - man page for claein (redhat section l)

Linux & Unix Commands - Search Man Pages
Man Page or Keyword Search:   man
Select Man Page Set:       apropos Keyword Search (sections above)


CLAEIN(l)					)					CLAEIN(l)

NAME
       CLAEIN  -  use  inverse iteration to find a right or left eigenvector corresponding to the
       eigenvalue W of a complex upper Hessenberg matrix H

SYNOPSIS
       SUBROUTINE CLAEIN( RIGHTV, NOINIT, N, H, LDH, W, V, B, LDB, RWORK, EPS3, SMLNUM, INFO )

	   LOGICAL	  NOINIT, RIGHTV

	   INTEGER	  INFO, LDB, LDH, N

	   REAL 	  EPS3, SMLNUM

	   COMPLEX	  W

	   REAL 	  RWORK( * )

	   COMPLEX	  B( LDB, * ), H( LDH, * ), V( * )

PURPOSE
       CLAEIN uses inverse iteration to find a right or left eigenvector corresponding to the ei-
       genvalue W of a complex upper Hessenberg matrix H.

ARGUMENTS
       RIGHTV	(input) LOGICAL
		= .TRUE. : compute right eigenvector;
		= .FALSE.: compute left eigenvector.

       NOINIT	(input) LOGICAL
		= .TRUE. : no initial vector supplied in V
		= .FALSE.: initial vector supplied in V.

       N       (input) INTEGER
	       The order of the matrix H.  N >= 0.

       H       (input) COMPLEX array, dimension (LDH,N)
	       The upper Hessenberg matrix H.

       LDH     (input) INTEGER
	       The leading dimension of the array H.  LDH >= max(1,N).

       W       (input) COMPLEX
	       The  eigenvalue	of  H whose corresponding right or left eigenvector is to be com-
	       puted.

       V       (input/output) COMPLEX array, dimension (N)
	       On entry, if NOINIT = .FALSE., V must contain a starting vector for inverse itera-
	       tion;  otherwise V need not be set.  On exit, V contains the computed eigenvector,
	       normalized so that the component of largest magnitude has magnitude  1;	here  the
	       magnitude of a complex number (x,y) is taken to be |x| + |y|.

       B       (workspace) COMPLEX array, dimension (LDB,N)

       LDB     (input) INTEGER
	       The leading dimension of the array B.  LDB >= max(1,N).

       RWORK   (workspace) REAL array, dimension (N)

       EPS3    (input) REAL
	       A small machine-dependent value which is used to perturb close eigenvalues, and to
	       replace zero pivots.

       SMLNUM  (input) REAL
	       A machine-dependent value close to the underflow threshold.

       INFO    (output) INTEGER
	       = 0:  successful exit
	       = 1:  inverse iteration did not converge; V is set to the last iterate.

LAPACK version 3.0			   15 June 2000 				CLAEIN(l)
Unix & Linux Commands & Man Pages : ©2000 - 2018 Unix and Linux Forums


All times are GMT -4. The time now is 08:44 PM.