LAPACK 3.12.0
LAPACK: Linear Algebra PACKage
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◆ droundup_lwork()

double precision function droundup_lwork ( integer  lwork)

DROUNDUP_LWORK

Purpose:
 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.
Parameters
[in]LWORKWorkspace size.
Author
Weslley Pereira, University of Colorado Denver, USA
Further Details:
  This routine was inspired in the method `magma_zmake_lwork` from MAGMA.
  \see https://bitbucket.org/icl/magma/src/master/control/magma_zauxiliary.cpp