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

6       DLABAD  - a input the values computed by DLAMCH for underflow and over‐
7       flow, and returns the square root of each of these values if the log of
8       LARGE is sufficiently large
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SYNOPSIS

11       SUBROUTINE DLABAD( SMALL, LARGE )
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13           DOUBLE         PRECISION LARGE, SMALL
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PURPOSE

16       DLABAD  takes  as input the values computed by DLAMCH for underflow and
17       overflow, and returns the square root of each of these  values  if  the
18       log  of  LARGE  is  sufficiently large.  This subroutine is intended to
19       identify machines with a large exponent range, such as the  Crays,  and
20       redefine  the  underflow  and overflow limits to be the square roots of
21       the values computed by  DLAMCH.   This  subroutine  is  needed  because
22       DLAMCH does not compensate for poor arithmetic in the upper half of the
23       exponent range, as is found on a Cray.
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ARGUMENTS

27       SMALL   (input/output) DOUBLE PRECISION
28               On entry, the underflow threshold as computed  by  DLAMCH.   On
29               exit, if LOG10(LARGE) is sufficiently large, the square root of
30               SMALL, otherwise unchanged.
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32       LARGE   (input/output) DOUBLE PRECISION
33               On entry, the overflow threshold as  computed  by  DLAMCH.   On
34               exit, if LOG10(LARGE) is sufficiently large, the square root of
35               LARGE, otherwise unchanged.
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39 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       DLABAD(1)