Provided by: liblapack-doc_3.3.1-1_all

**NAME**

LAPACK-3 - routine i not for general use

**SYNOPSIS**

LOGICAL FUNCTION SLAISNAN( SIN1, SIN2 ) REAL SIN1, SIN2

**PURPOSE**

This routine is not for general use. It exists solely to avoid over-optimization in SISNAN. SLAISNAN 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**

SIN1 (input) REAL SIN2 (input) REAL Two numbers to compare for inequality. LAPACK auxiliary routine (version 3.2.2) April 2011 SLAISNAN(3lapack)