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*> \brief \b DROUNDUP_LWORK
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
* Definition:
* ===========
*
* DOUBLE PRECISION FUNCTION DROUNDUP_LWORK( LWORK )
*
* .. Scalar Arguments ..
* INTEGER LWORK
* ..
*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
*> DROUNDUP_LWORK deals with a subtle bug with returning LWORK as a Float.
*> This routine guarantees it is rounded up instead of down by
*> multiplying LWORK by 1+eps when it is necessary, where eps is the relative machine precision.
*> E.g.,
*>
*> float( 9007199254740993 ) == 9007199254740992
*> float( 9007199254740993 ) * (1.+eps) == 9007199254740994
*>
*> \return DROUNDUP_LWORK
*> \verbatim
*> DROUNDUP_LWORK >= LWORK.
*> DROUNDUP_LWORK is guaranteed to have zero decimal part.
*> \endverbatim
*
* Arguments:
* ==========
*
*> \param[in] LWORK Workspace size.
*
* Authors:
* ========
*
*> \author Weslley Pereira, University of Colorado Denver, USA
*
*> \ingroup roundup_lwork
*
*> \par Further Details:
* =====================
*>
*> \verbatim
*> This routine was inspired in the method `magma_zmake_lwork` from MAGMA.
*> \see https://bitbucket.org/icl/magma/src/master/control/magma_zauxiliary.cpp
*> \endverbatim
*
* =====================================================================
DOUBLE PRECISION FUNCTION DROUNDUP_LWORK( LWORK )
*
* -- LAPACK auxiliary routine --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
* .. Scalar Arguments ..
INTEGER LWORK
* ..
*
* =====================================================================
* ..
* .. Intrinsic Functions ..
INTRINSIC EPSILON, DBLE, INT
* ..
* .. Executable Statements ..
* ..
DROUNDUP_LWORK = DBLE( LWORK )
*
IF( INT( DROUNDUP_LWORK ) .LT. LWORK ) THEN
* Force round up of LWORK
DROUNDUP_LWORK = DROUNDUP_LWORK *
$ ( 1.0D+0 + EPSILON(0.0D+0) )
ENDIF
*
RETURN
*
* End of DROUNDUP_LWORK
*
END
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