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      SUBROUTINE DLABAD( SMALL, LARGE )
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*
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*  -- LAPACK auxiliary routine (version 3.2) --
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*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
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*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
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*     November 2006
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*
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*     .. Scalar Arguments ..
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      DOUBLE PRECISION   LARGE, SMALL
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*     ..
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*
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*  Purpose
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*  =======
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*
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*  DLABAD takes as input the values computed by DLAMCH for underflow and
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*  overflow, and returns the square root of each of these values if the
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*  log of LARGE is sufficiently large.  This subroutine is intended to
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*  identify machines with a large exponent range, such as the Crays, and
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*  redefine the underflow and overflow limits to be the square roots of
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*  the values computed by DLAMCH.  This subroutine is needed because
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*  DLAMCH does not compensate for poor arithmetic in the upper half of
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*  the exponent range, as is found on a Cray.
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*
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*  Arguments
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*  =========
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*
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*  SMALL   (input/output) DOUBLE PRECISION
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*          On entry, the underflow threshold as computed by DLAMCH.
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*          On exit, if LOG10(LARGE) is sufficiently large, the square
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*          root of SMALL, otherwise unchanged.
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*
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*  LARGE   (input/output) DOUBLE PRECISION
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*          On entry, the overflow threshold as computed by DLAMCH.
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*          On exit, if LOG10(LARGE) is sufficiently large, the square
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*          root of LARGE, otherwise unchanged.
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*
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*  =====================================================================
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*
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*     .. Intrinsic Functions ..
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      INTRINSIC          LOG10, SQRT
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*     ..
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*     .. Executable Statements ..
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*
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*     If it looks like we're on a Cray, take the square root of
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*     SMALL and LARGE to avoid overflow and underflow problems.
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*
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      IF( LOG10( LARGE ).GT.2000.D0 ) THEN
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         SMALL = SQRT( SMALL )
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         LARGE = SQRT( LARGE )
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      END IF
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*
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      RETURN
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*
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*     End of DLABAD
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*
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      END