DLAISNAN(3)    LAPACK routine of NEC Numeric Library Collection    DLAISNAN(3)



NAME
       DLAISNAN

SYNOPSIS
       LOGICAL FUNCTION DLAISNAN (DIN1, DIN2)



PURPOSE
            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.




ARGUMENTS
           DIN1      (input)
                     DIN1 is DOUBLE PRECISION

           DIN2      (input)
                     DIN2 is DOUBLE PRECISION
                     Two numbers to compare for inequality.



LAPACK routine                  31 October 2017                    DLAISNAN(3)