dlaisnan()

logical function dlaisnan	(	double precision, intent(in)	din1,
		double precision, intent(in)	din2 )

DLAISNAN tests input for NaN by comparing two arguments for inequality.

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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.
!> 

Parameters

[in]	DIN1	!> DIN1 is DOUBLE PRECISION !>
[in]	DIN2	!> DIN2 is DOUBLE PRECISION !> Two numbers to compare for inequality. !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 71 of file dlaisnan.f.

*
*  -- LAPACK auxiliary routine --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
*     .. Scalar Arguments ..
      DOUBLE PRECISION, INTENT(IN) :: DIN1, DIN2
*     ..
*
*  =====================================================================
*
*  .. Executable Statements ..
      dlaisnan = (din1.NE.din2)
      RETURN

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