SLAED6(l)								 )								 SLAED6(l)

NAME

       SLAED6  -  compute  the positive or negative root (closest to the origin) of z(1) z(2) z(3) f(x) = rho + --------- + ---------- + ---------
       d(1)-x d(2)-x d(3)-x  It is assumed that  if ORGATI = .true

SYNOPSIS

       SUBROUTINE SLAED6( KNITER, ORGATI, RHO, D, Z, FINIT, TAU, INFO )

	   LOGICAL	  ORGATI

	   INTEGER	  INFO, KNITER

	   REAL 	  FINIT, RHO, TAU

	   REAL 	  D( 3 ), Z( 3 )

PURPOSE

       SLAED6 computes the positive or negative root (closest to the origin) of z(1) z(2) z(3) f(x) = rho + ---------  +  ----------  +  ---------
       d(1)-x d(2)-x d(3)-x It is assumed that if ORGATI = .true. the root is between d(2) and d(3);	   otherwise it is between d(1) and d(2)

       This  routine  will be called by SLAED4 when necessary. In most cases, the root sought is the smallest in magnitude, though it might not be
       in some extremely rare situations.

ARGUMENTS

       KNITER	    (input) INTEGER
		    Refer to SLAED4 for its significance.

       ORGATI	    (input) LOGICAL
		    If ORGATI is true, the needed root is between d(2) and d(3); otherwise it is between d(1) and d(2).  See  SLAED4  for  further
		    details.

       RHO	    (input) REAL
		    Refer to the equation f(x) above.

       D	    (input) REAL array, dimension (3)
		    D satisfies d(1) < d(2) < d(3).

       Z	    (input) REAL array, dimension (3)
		    Each of the elements in z must be positive.

       FINIT	    (input) REAL
		    The value of f at 0. It is more accurate than the one evaluated inside this routine (if someone wants to do so).

       TAU	    (output) REAL
		    The root of the equation f(x).

       INFO	    (output) INTEGER
		    = 0: successful exit
		    > 0: if INFO = 1, failure to converge

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 							 SLAED6(l)