`01: `**LOGICAL** **FUNCTION** **DLAISNAN**(DIN1,DIN2)
02: ***
03: ** -- LAPACK auxiliary routine (version 3.2) --*
04: ** -- LAPACK is a software package provided by Univ. of Tennessee, --*
05: ** -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--*
06: ** November 2006*
07: ***
08: ** .. Scalar Arguments ..*
09: DOUBLE PRECISION DIN1,DIN2
10: ** ..*
11: ***
12: ** Purpose*
13: ** =======*
14: ***
15: ** This routine is not for general use. It exists solely to avoid*
16: ** over-optimization in DISNAN.*
17: ***
18: ** DLAISNAN checks for NaNs by comparing its two arguments for*
19: ** inequality. NaN is the only floating-point value where NaN != NaN*
20: ** returns .TRUE. To check for NaNs, pass the same variable as both*
21: ** arguments.*
22: ***
23: ** A compiler must assume that the two arguments are*
24: ** not the same variable, and the test will not be optimized away.*
25: ** Interprocedural or whole-program optimization may delete this*
26: ** test. The ISNAN functions will be replaced by the correct*
27: ** Fortran 03 intrinsic once the intrinsic is widely available.*
28: ***
29: ** Arguments*
30: ** =========*
31: ***
32: ** DIN1 (input) DOUBLE PRECISION*
33: ** DIN2 (input) DOUBLE PRECISION*
34: ** Two numbers to compare for inequality.*
35: ***
36: ** =====================================================================*
37: ***
38: ** .. Executable Statements ..*
39: DLAISNAN = (DIN1.NE.DIN2)
40: **RETURN**
41: **END**
42: