/* -- translated by f2c (version 20100827).
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*/
#include "f2c.h"
/* > \brief \b DLABAD
=========== DOCUMENTATION ===========
Online html documentation available at
http://www.netlib.org/lapack/explore-html/
> \htmlonly
> Download DLABAD + dependencies
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f">
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f">
> [TXT]</a>
> \endhtmlonly
Definition:
===========
SUBROUTINE DLABAD( SMALL, LARGE )
DOUBLE PRECISION LARGE, SMALL
> \par Purpose:
=============
>
> \verbatim
>
> DLABAD takes as input the values computed by DLAMCH for underflow and
> overflow, and returns the square root of each of these values if the
> log of LARGE is sufficiently large. This subroutine is intended to
> identify machines with a large exponent range, such as the Crays, and
> redefine the underflow and overflow limits to be the square roots of
> the values computed by DLAMCH. This subroutine is needed because
> DLAMCH does not compensate for poor arithmetic in the upper half of
> the exponent range, as is found on a Cray.
> \endverbatim
Arguments:
==========
> \param[in,out] SMALL
> \verbatim
> SMALL is DOUBLE PRECISION
> On entry, the underflow threshold as computed by DLAMCH.
> On exit, if LOG10(LARGE) is sufficiently large, the square
> root of SMALL, otherwise unchanged.
> \endverbatim
>
> \param[in,out] LARGE
> \verbatim
> LARGE is DOUBLE PRECISION
> On entry, the overflow threshold as computed by DLAMCH.
> On exit, if LOG10(LARGE) is sufficiently large, the square
> root of LARGE, otherwise unchanged.
> \endverbatim
Authors:
========
> \author Univ. of Tennessee
> \author Univ. of California Berkeley
> \author Univ. of Colorado Denver
> \author NAG Ltd.
> \date November 2011
> \ingroup auxOTHERauxiliary
=====================================================================
Subroutine */ int igraphdlabad_(doublereal *small, doublereal *large)
{
/* Builtin functions */
double d_lg10(doublereal *), sqrt(doublereal);
/* -- LAPACK auxiliary routine (version 3.4.0) --
-- LAPACK is a software package provided by Univ. of Tennessee, --
-- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
November 2011
=====================================================================
If it looks like we're on a Cray, take the square root of
SMALL and LARGE to avoid overflow and underflow problems. */
if (d_lg10(large) > 2e3) {
*small = sqrt(*small);
*large = sqrt(*large);
}
return 0;
/* End of DLABAD */
} /* igraphdlabad_ */