.TH "SRC/slaed6.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
SRC/slaed6.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBslaed6\fP (kniter, orgati, rho, d, z, finit, tau, info)"
.br
.RI "\fBSLAED6\fP used by SSTEDC\&. Computes one Newton step in solution of the secular equation\&. "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine slaed6 (integer kniter, logical orgati, real rho, real, dimension( 3 ) d, real, dimension( 3 ) z, real finit, real tau, integer info)"

.PP
\fBSLAED6\fP used by SSTEDC\&. Computes one Newton step in solution of the secular equation\&.  
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
!>
!> 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\&.
!> 
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIKNITER\fP 
.PP
.nf
!>          KNITER is INTEGER
!>               Refer to SLAED4 for its significance\&.
!> 
.fi
.PP
.br
\fIORGATI\fP 
.PP
.nf
!>          ORGATI is 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\&.
!> 
.fi
.PP
.br
\fIRHO\fP 
.PP
.nf
!>          RHO is REAL
!>               Refer to the equation f(x) above\&.
!> 
.fi
.PP
.br
\fID\fP 
.PP
.nf
!>          D is REAL array, dimension (3)
!>               D satisfies d(1) < d(2) < d(3)\&.
!> 
.fi
.PP
.br
\fIZ\fP 
.PP
.nf
!>          Z is REAL array, dimension (3)
!>               Each of the elements in z must be positive\&.
!> 
.fi
.PP
.br
\fIFINIT\fP 
.PP
.nf
!>          FINIT is REAL
!>               The value of f at 0\&. It is more accurate than the one
!>               evaluated inside this routine (if someone wants to do
!>               so)\&.
!> 
.fi
.PP
.br
\fITAU\fP 
.PP
.nf
!>          TAU is REAL
!>               The root of the equation f(x)\&.
!> 
.fi
.PP
.br
\fIINFO\fP 
.PP
.nf
!>          INFO is INTEGER
!>               = 0: successful exit
!>               > 0: if INFO = 1, failure to converge
!> 
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 

.PP
Univ\&. of California Berkeley 

.PP
Univ\&. of Colorado Denver 

.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
!>
!>  10/02/03: This version has a few statements commented out for thread
!>  safety (machine parameters are computed on each entry)\&. SJH\&.
!>
!>  05/10/06: Modified from a new version of Ren-Cang Li, use
!>     Gragg-Thornton-Warner cubic convergent scheme for better stability\&.
!> 
.fi
.PP
 
.RE
.PP
\fBContributors:\fP
.RS 4
Ren-Cang Li, Computer Science Division, University of California at Berkeley, USA 
.RE
.PP

.PP
Definition at line \fB139\fP of file \fBslaed6\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.