dlaisnan.F90 Source File


Source Code

#include "ESMF_LapackBlas.inc"
!> \brief \b DLAISNAN
!
!  =========== DOCUMENTATION ===========
!
! Online html documentation available at
!            http://www.netlib.org/lapack/explore-html/
!
!> \htmlonly
!> Download DLAISNAN + dependencies
!> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlaisnan.f">
!> [TGZ]</a>
!> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlaisnan.f">
!> [ZIP]</a>
!> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlaisnan.f">
!> [TXT]</a>
!> \endhtmlonly
!
!  Definition:
!  ===========
!
!       LOGICAL FUNCTION DLAISNAN( DIN1, DIN2 )
!
!       .. Scalar Arguments ..
!       DOUBLE PRECISION   DIN1, DIN2
!       ..
!
!
!> \par Purpose:
!  =============
!>
!> \verbatim
!>
!> This routine is not for general use.  It exists solely to avoid
!> over-optimization in DISNAN.
!>
!> DLAISNAN checks for NaNs by comparing its two arguments for
!> inequality.  NaN is the only floating-point value where NaN != NaN
!> returns .TRUE.  To check for NaNs, pass the same variable as both
!> arguments.
!>
!> A compiler must assume that the two arguments are
!> not the same variable, and the test will not be optimized away.
!> Interprocedural or whole-program optimization may delete this
!> test.  The ISNAN functions will be replaced by the correct
!> Fortran 03 intrinsic once the intrinsic is widely available.
!> \endverbatim
!
!  Arguments:
!  ==========
!
!> \param[in] DIN1
!> \verbatim
!>          DIN1 is DOUBLE PRECISION
!> \endverbatim
!>
!> \param[in] DIN2
!> \verbatim
!>          DIN2 is DOUBLE PRECISION
!>          Two numbers to compare for inequality.
!> \endverbatim
!
!  Authors:
!  ========
!
!> \author Univ. of Tennessee
!> \author Univ. of California Berkeley
!> \author Univ. of Colorado Denver
!> \author NAG Ltd.
!
!> \date November 2011
!
!> \ingroup auxOTHERauxiliary
!
!  =====================================================================
      LOGICAL FUNCTION DLAISNAN( DIN1, DIN2 )
!
!  -- 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
!
!     .. Scalar Arguments ..
      DOUBLE PRECISION   DIN1, DIN2
!     ..
!
!  =====================================================================
!
!  .. Executable Statements ..
      DLAISNAN = (DIN1.NE.DIN2)
      RETURN
      END