| *> \brief \b DLAISNAN tests input for NaN by comparing two arguments for inequality. |
| * |
| * =========== 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 September 2012 |
| * |
| *> \ingroup auxOTHERauxiliary |
| * |
| * ===================================================================== |
| LOGICAL FUNCTION DLAISNAN( DIN1, DIN2 ) |
| * |
| * -- LAPACK auxiliary routine (version 3.4.2) -- |
| * -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| * September 2012 |
| * |
| * .. Scalar Arguments .. |
| DOUBLE PRECISION DIN1, DIN2 |
| * .. |
| * |
| * ===================================================================== |
| * |
| * .. Executable Statements .. |
| DLAISNAN = (DIN1.NE.DIN2) |
| RETURN |
| END |
