DLASQ4 - compute an approximation TAU to the smallest
eigenvalue using values of d from the previous transform
SYNOPSIS
SUBROUTINE DLASQ4( I0, N0, Z, PP, N0IN, DMIN, DMIN1,
DMIN2, DN, DN1, DN2, TAU, TTYPE )
INTEGER I0, N0, N0IN, PP, TTYPE
DOUBLE PRECISION DMIN, DMIN1, DMIN2, DN, DN1,
DN2, TAU
DOUBLE PRECISION Z( * )
PURPOSE
DLASQ4 computes an approximation TAU to the smallest
eigenvalue using values of d from the previous transform.
I0 (input) INTEGER
First index.
N0 (input) INTEGER
Last index.
Z (input) DOUBLE PRECISION array, dimension ( 4*N )
Z holds the qd array.
PP (input) INTEGER
PP=0 for ping, PP=1 for pong.
NOIN (input) INTEGER
The value of N0 at start of EIGTEST.
DMIN (input) DOUBLE PRECISION
Minimum value of d.
DMIN1 (input) DOUBLE PRECISION
Minimum value of d, excluding D( N0 ).
DMIN2 (input) DOUBLE PRECISION
Minimum value of d, excluding D( N0 ) and D( N0-1 ).
DN (input) DOUBLE PRECISION
d(N)
DN1 (input) DOUBLE PRECISION
d(N-1)
DN2 (input) DOUBLE PRECISION
d(N-2)
TAU (output) DOUBLE PRECISION
This is the shift.
Shift type.
FURTHER DETAILS
Man(1) output converted with
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