1DLASQ6(1)LAPACK routine (version 3.2)                                 DLASQ6(1)
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NAME

6       DLASQ6  - computes one dqd (shift equal to zero) transform in ping-pong
7       form, with protection against underflow and overflow
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SYNOPSIS

10       SUBROUTINE DLASQ6( I0, N0, Z, PP, DMIN, DMIN1, DMIN2, DN, DNM1, DNM2 )
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12           INTEGER        I0, N0, PP
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14           DOUBLE         PRECISION DMIN, DMIN1, DMIN2, DN, DNM1, DNM2
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16           DOUBLE         PRECISION Z( * )
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PURPOSE

19       DLASQ6 computes one dqd (shift equal to zero)  transform  in  ping-pong
20       form, with protection against underflow and overflow.
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ARGUMENTS

23       I0    (input) INTEGER
24             First index.
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26       N0    (input) INTEGER
27             Last index.
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29       Z     (input) DOUBLE PRECISION array, dimension ( 4*N )
30             Z holds the qd array. EMIN is stored in Z(4*N0) to avoid an extra
31             argument.
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33       PP    (input) INTEGER
34             PP=0 for ping, PP=1 for pong.
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36       DMIN  (output) DOUBLE PRECISION
37             Minimum value of d.   DMIN1  (output)  DOUBLE  PRECISION  Minimum
38             value  of  d, excluding D( N0 ).  DMIN2 (output) DOUBLE PRECISION
39             Minimum value of d, excluding D( N0 ) and D( N0-1 ).
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41       DN    (output) DOUBLE PRECISION
42             d(N0), the last value of d.
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44       DNM1  (output) DOUBLE PRECISION
45             d(N0-1).
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47       DNM2  (output) DOUBLE PRECISION
48             d(N0-2).
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52 LAPACK routine (version 3.2)    November 2008                       DLASQ6(1)