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.TH SLASQ4 l "15 June 2000" "LAPACK version 3.0" ")"
.SH NAME
SLASQ4 - compute an approximation TAU to the smallest eigenvalue using values of d from the previous transform
.SH SYNOPSIS
.TP 19
SUBROUTINE SLASQ4(
I0, N0, Z, PP, N0IN, DMIN, DMIN1, DMIN2, DN,
DN1, DN2, TAU, TTYPE )
.TP 19
.ti +4
INTEGER
I0, N0, N0IN, PP, TTYPE
.TP 19
.ti +4
REAL
DMIN, DMIN1, DMIN2, DN, DN1, DN2, TAU
.TP 19
.ti +4
REAL
Z( * )
.SH PURPOSE
SLASQ4 computes an approximation TAU to the smallest eigenvalue using values of d from the previous transform.
I0 (input) INTEGER
.br
First index.
.br
N0 (input) INTEGER
.br
Last index.
.br
Z (input) REAL array, dimension ( 4*N )
.br
Z holds the qd array.
.br
PP (input) INTEGER
.br
PP=0 for ping, PP=1 for pong.
.br
NOIN (input) INTEGER
.br
The value of N0 at start of EIGTEST.
.br
DMIN (input) REAL
.br
Minimum value of d.
.br
DMIN1 (input) REAL
.br
Minimum value of d, excluding D( N0 ).
.br
DMIN2 (input) REAL
.br
Minimum value of d, excluding D( N0 ) and D( N0-1 ).
DN (input) REAL
.br
d(N)
.br
DN1 (input) REAL
.br
d(N-1)
.br
DN2 (input) REAL
.br
d(N-2)
.br
TAU (output) REAL
.br
This is the shift.
.br
TTYPE (output) INTEGER
.br
Shift type.
.br
.SH FURTHER DETAILS
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