CXML
        	    
LAPACK version 3.0
slasq4(3)

PURPOSE
  SLASQ4 - compute an approximation TAU to the smallest eigenvalue using
  values of d from the previous transform

SYNTAX
  SUBROUTINE SLASQ4( I0, N0, Z, PP, N0IN, DMIN, DMIN1, DMIN2, DN, DN1, DN2,
		     TAU, TTYPE )

      INTEGER	     I0, N0, N0IN, PP, TTYPE

      REAL	     DMIN, DMIN1, DMIN2, DN, DN1, DN2, TAU

      REAL	     Z( * )

DESCRIPTION
  SLASQ4 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) REAL 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) REAL
	Minimum value of d.

  DMIN1 (input) REAL
	Minimum value of d, excluding D( N0 ).

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

  DN	(input) REAL
	d(N)

  DN1	(input) REAL
	d(N-1)

  DN2	(input) REAL
	d(N-2)

  TAU	(output) REAL
	This is the shift.

  TTYPE (output) INTEGER
	Shift type.

FURTHER DETAILS