1DLASQ6(1)           LAPACK auxiliary routine (version 3.1)           DLASQ6(1)
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NAME

6       DLASQ6  -  one  dqd  (shift equal to zero) transform in ping-pong form,
7       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

24       I0    (input) INTEGER
25             First index.
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27       N0    (input) INTEGER
28             Last index.
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30       Z     (input) DOUBLE PRECISION array, dimension ( 4*N )
31             Z holds the qd array. EMIN is stored in Z(4*N0) to avoid an extra
32             argument.
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34       PP    (input) INTEGER
35             PP=0 for ping, PP=1 for pong.
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37       DMIN  (output) DOUBLE PRECISION
38             Minimum value of d.
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40             DMIN1 (output) DOUBLE PRECISION Minimum value of d, excluding  D(
41             N0 ).
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43             DMIN2  (output) DOUBLE PRECISION Minimum value of d, excluding D(
44             N0 ) and D( N0-1 ).
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46       DN    (output) DOUBLE PRECISION
47             d(N0), the last value of d.
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49       DNM1  (output) DOUBLE PRECISION
50             d(N0-1).
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52       DNM2  (output) DOUBLE PRECISION
53             d(N0-2).
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57 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       DLASQ6(1)