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Annotation of rpl/lapack/lapack/dlaisnan.f, revision 1.9

1.9     ! bertrand    1: *> \brief \b DLAISNAN
        !             2: *
        !             3: *  =========== DOCUMENTATION ===========
        !             4: *
        !             5: * Online html documentation available at 
        !             6: *            http://www.netlib.org/lapack/explore-html/ 
        !             7: *
        !             8: *> \htmlonly
        !             9: *> Download DLAISNAN + dependencies 
        !            10: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlaisnan.f"> 
        !            11: *> [TGZ]</a> 
        !            12: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlaisnan.f"> 
        !            13: *> [ZIP]</a> 
        !            14: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlaisnan.f"> 
        !            15: *> [TXT]</a>
        !            16: *> \endhtmlonly 
        !            17: *
        !            18: *  Definition:
        !            19: *  ===========
        !            20: *
        !            21: *       LOGICAL FUNCTION DLAISNAN( DIN1, DIN2 )
        !            22: * 
        !            23: *       .. Scalar Arguments ..
        !            24: *       DOUBLE PRECISION   DIN1, DIN2
        !            25: *       ..
        !            26: *  
        !            27: *
        !            28: *> \par Purpose:
        !            29: *  =============
        !            30: *>
        !            31: *> \verbatim
        !            32: *>
        !            33: *> This routine is not for general use.  It exists solely to avoid
        !            34: *> over-optimization in DISNAN.
        !            35: *>
        !            36: *> DLAISNAN checks for NaNs by comparing its two arguments for
        !            37: *> inequality.  NaN is the only floating-point value where NaN != NaN
        !            38: *> returns .TRUE.  To check for NaNs, pass the same variable as both
        !            39: *> arguments.
        !            40: *>
        !            41: *> A compiler must assume that the two arguments are
        !            42: *> not the same variable, and the test will not be optimized away.
        !            43: *> Interprocedural or whole-program optimization may delete this
        !            44: *> test.  The ISNAN functions will be replaced by the correct
        !            45: *> Fortran 03 intrinsic once the intrinsic is widely available.
        !            46: *> \endverbatim
        !            47: *
        !            48: *  Arguments:
        !            49: *  ==========
        !            50: *
        !            51: *> \param[in] DIN1
        !            52: *> \verbatim
        !            53: *>          DIN1 is DOUBLE PRECISION
        !            54: *> \endverbatim
        !            55: *>
        !            56: *> \param[in] DIN2
        !            57: *> \verbatim
        !            58: *>          DIN2 is DOUBLE PRECISION
        !            59: *>          Two numbers to compare for inequality.
        !            60: *> \endverbatim
        !            61: *
        !            62: *  Authors:
        !            63: *  ========
        !            64: *
        !            65: *> \author Univ. of Tennessee 
        !            66: *> \author Univ. of California Berkeley 
        !            67: *> \author Univ. of Colorado Denver 
        !            68: *> \author NAG Ltd. 
        !            69: *
        !            70: *> \date November 2011
        !            71: *
        !            72: *> \ingroup auxOTHERauxiliary
        !            73: *
        !            74: *  =====================================================================
1.5       bertrand   75:       LOGICAL FUNCTION DLAISNAN( DIN1, DIN2 )
1.1       bertrand   76: *
1.9     ! bertrand   77: *  -- LAPACK auxiliary routine (version 3.4.0) --
1.1       bertrand   78: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
                     79: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
1.9     ! bertrand   80: *     November 2011
1.1       bertrand   81: *
                     82: *     .. Scalar Arguments ..
1.5       bertrand   83:       DOUBLE PRECISION   DIN1, DIN2
1.1       bertrand   84: *     ..
                     85: *
                     86: *  =====================================================================
                     87: *
                     88: *  .. Executable Statements ..
                     89:       DLAISNAN = (DIN1.NE.DIN2)
                     90:       RETURN
                     91:       END