1DLASQ4(1)LAPACK routine (version 3.2)                                 DLASQ4(1)
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NAME

6       DLASQ4 - computes an approximation TAU to the smallest eigenvalue using
7       values of d from the previous transform
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SYNOPSIS

10       SUBROUTINE DLASQ4( I0, N0, Z, PP, N0IN, DMIN, DMIN1,  DMIN2,  DN,  DN1,
11                          DN2, TAU, TTYPE, G )
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13           INTEGER        I0, N0, N0IN, PP, TTYPE
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15           DOUBLE         PRECISION DMIN, DMIN1, DMIN2, DN, DN1, DN2, G, TAU
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17           DOUBLE         PRECISION Z( * )
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PURPOSE

20       DLASQ4  computes  an approximation TAU to the smallest eigenvalue using
21       values of d from the previous transform.  I0    (input) INTEGER
22             First index.
23       N0    (input) INTEGER
24             Last index.
25       Z     (input) DOUBLE PRECISION array, dimension ( 4*N )
26             Z holds the qd array.
27       PP    (input) INTEGER
28             PP=0 for ping, PP=1 for pong.
29       NOIN  (input) INTEGER
30             The value of N0 at start of EIGTEST.
31       DMIN  (input) DOUBLE PRECISION
32             Minimum value of d.
33       DMIN1 (input) DOUBLE PRECISION
34             Minimum value of d, excluding D( N0 ).
35       DMIN2 (input) DOUBLE PRECISION
36             Minimum value of d,  excluding  D(  N0  )  and  D(  N0-1  ).   DN
37       (input) DOUBLE PRECISION
38             d(N)
39       DN1   (input) DOUBLE PRECISION
40             d(N-1)
41       DN2   (input) DOUBLE PRECISION
42             d(N-2)
43       TAU   (output) DOUBLE PRECISION
44             This is the shift.
45       TTYPE (output) INTEGER
46             Shift type.
47       G     (input/output) REAL
48             G is passed as an argument in order to save its value between
49             calls to DLASQ4.
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FURTHER DETAILS

52 LAPACK routine (version 3.2)    November 2008                       DLASQ4(1)