1SLABAD(1) LAPACK auxiliary routine (version 3.1) SLABAD(1)
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6 SLABAD - a input the values computed by SLAMCH 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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11 SUBROUTINE SLABAD( SMALL, LARGE )
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13 REAL LARGE, SMALL
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16 SLABAD takes as input the values computed by SLAMCH 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 SLAMCH. This subroutine is needed because
22 SLAMCH 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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27 SMALL (input/output) REAL
28 On entry, the underflow threshold as computed by SLAMCH. 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) REAL
33 On entry, the overflow threshold as computed by SLAMCH. 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 SLABAD(1)