dlaed5(l) [redhat man page]

DLAED5(l)								 )								 DLAED5(l)

NAME

       DLAED5  -  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)

SYNOPSIS

       SUBROUTINE DLAED5( I, D, Z, DELTA, RHO, DLAM )

	   INTEGER	  I

	   DOUBLE	  PRECISION DLAM, RHO

	   DOUBLE	  PRECISION D( 2 ), DELTA( 2 ), Z( 2 )

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 *  trans-
       pose(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.

FURTHER DETAILS

       Based on contributions by
	  Ren-Cang Li, Computer Science Division, University of California
	  at Berkeley, USA

LAPACK version 3.0						   15 June 2000 							 DLAED5(l)

dlaed5.f(3)							      LAPACK							       dlaed5.f(3)

NAME

       dlaed5.f -

SYNOPSIS

   Functions/Subroutines
       subroutine dlaed5 (I, D, Z, DELTA, RHO, DLAM)
	   DLAED5

Function/Subroutine Documentation
   subroutine dlaed5 (integerI, double precision, dimension( 2 )D, double precision, dimension( 2 )Z, double precision, dimension( 2 )DELTA,
       double precisionRHO, double precisionDLAM)
       DLAED5

       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.

       Parameters:
	   I

		     I is INTEGER
		    The index of the eigenvalue to be computed.  I = 1 or I = 2.

	   D

		     D is DOUBLE PRECISION array, dimension (2)
		    The original eigenvalues.  We assume D(1) < D(2).

	   Z

		     Z is DOUBLE PRECISION array, dimension (2)
		    The components of the updating vector.

	   DELTA

		     DELTA is DOUBLE PRECISION array, dimension (2)
		    The vector DELTA contains the information necessary
		    to construct the eigenvectors.

	   RHO

		     RHO is DOUBLE PRECISION
		    The scalar in the symmetric updating formula.

	   DLAM

		     DLAM is DOUBLE PRECISION
		    The computed lambda_I, the I-th updated eigenvalue.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Contributors:
	   Ren-Cang Li, Computer Science Division, University of California at Berkeley, USA

       Definition at line 109 of file dlaed5.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.1							  Sun May 26 2013						       dlaed5.f(3)