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NAME
     dlaed6 - compute the positive or negative root  (closest  to
     the  origin)  of  f(x)  =  rho + (z(1) / (d(1)-x)) + (z(2) /
     (d(2)-x)) + (z(3) /  (d(3)-x))   It  is  assumed  that    if
     ORGATI = .true

SYNOPSIS
     SUBROUTINE DLAED6( KNITER, ORGATI, RHO, D,  Z,  FINIT,  TAU,
               INFO )

     LOGICAL ORGATI

     INTEGER INFO, KNITER

     DOUBLE PRECISION FINIT, RHO, TAU

     DOUBLE PRECISION D( 3 ), Z( 3 )



     #include <sunperf.h>

     void dlaed6(int kniter, int orgati, double drho, double  *d,
               double *dz, double finit, double *tau,
                int *info) ;

PURPOSE
     DLAED6 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

     otherwise it is between d(1) and d(2)

     This routine will be called by  DLAED4  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 DLAED4 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 DLAED4 for further details.

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

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

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

     FINIT     (input) DOUBLE PRECISION
               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) DOUBLE PRECISION
               The root of the equation f(x).

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

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