!>
!> SLASQ4 computes an approximation TAU to the smallest eigenvalue
!> using values of d from the previous transform.
!> 

I0

!>          I0 is INTEGER
!>        First index.
!> 

N0

!>          N0 is INTEGER
!>        Last index.
!> 

Z

!>          Z is REAL array, dimension ( 4*N0 )
!>        Z holds the qd array.
!> 

PP

!>          PP is INTEGER
!>        PP=0 for ping, PP=1 for pong.
!> 

N0IN

!>          N0IN is INTEGER
!>        The value of N0 at start of EIGTEST.
!> 

DMIN

!>          DMIN is REAL
!>        Minimum value of d.
!> 

DMIN1

!>          DMIN1 is REAL
!>        Minimum value of d, excluding D( N0 ).
!> 

DMIN2

!>          DMIN2 is REAL
!>        Minimum value of d, excluding D( N0 ) and D( N0-1 ).
!> 

DN

!>          DN is REAL
!>        d(N)
!> 

DN1

!>          DN1 is REAL
!>        d(N-1)
!> 

DN2

!>          DN2 is REAL
!>        d(N-2)
!> 

TAU

!>          TAU is REAL
!>        This is the shift.
!> 

TTYPE

!>          TTYPE is INTEGER
!>        Shift type.
!> 

G

!>          G is REAL
!>        G is passed as an argument in order to save its value between
!>        calls to SLASQ4.
!> 

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

!>
!>  CNST1 = 9/16
!>