DLAISNAN(1) LAPACK auxiliary routine (version 3.2) DLAISNAN(1)NAME
DLAISNAN - routine i not for general use
LOGICAL FUNCTION DLAISNAN(DIN1,DIN2)
DOUBLE PRECISION DIN1,DIN2
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. Inter‐
procedural 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.
DIN1 (input) DOUBLE PRECISION
DIN2 (input) DOUBLE PRECISION Two numbers to compare for
LAPACK auxiliary routine (versioNovember 2008 DLAISNAN(1)