1 /* dlaisnan.f -- translated by f2c (version 20061008).
2    You must link the resulting object file with libf2c:
3 	on Microsoft Windows system, link with libf2c.lib;
4 	on Linux or Unix systems, link with .../path/to/libf2c.a -lm
5 	or, if you install libf2c.a in a standard place, with -lf2c -lm
6 	-- in that order, at the end of the command line, as in
7 		cc *.o -lf2c -lm
8 	Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
9 
10 		http://www.netlib.org/f2c/libf2c.zip
11 */
12 
13 #include "f2c.h"
14 #include "blaswrap.h"
15 
dlaisnan_(doublereal * din1,doublereal * din2)16 logical dlaisnan_(doublereal *din1, doublereal *din2)
17 {
18     /* System generated locals */
19     logical ret_val;
20 
21 
22 /*  -- LAPACK auxiliary routine (version 3.2) -- */
23 /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
24 /*     November 2006 */
25 
26 /*     .. Scalar Arguments .. */
27 /*     .. */
28 
29 /*  Purpose */
30 /*  ======= */
31 
32 /*  This routine is not for general use.  It exists solely to avoid */
33 /*  over-optimization in DISNAN. */
34 
35 /*  DLAISNAN checks for NaNs by comparing its two arguments for */
36 /*  inequality.  NaN is the only floating-point value where NaN != NaN */
37 /*  returns .TRUE.  To check for NaNs, pass the same variable as both */
38 /*  arguments. */
39 
40 /*  A compiler must assume that the two arguments are */
41 /*  not the same variable, and the test will not be optimized away. */
42 /*  Interprocedural or whole-program optimization may delete this */
43 /*  test.  The ISNAN functions will be replaced by the correct */
44 /*  Fortran 03 intrinsic once the intrinsic is widely available. */
45 
46 /*  Arguments */
47 /*  ========= */
48 
49 /*  DIN1     (input) DOUBLE PRECISION */
50 /*  DIN2     (input) DOUBLE PRECISION */
51 /*          Two numbers to compare for inequality. */
52 
53 /*  ===================================================================== */
54 
55 /*  .. Executable Statements .. */
56     ret_val = *din1 != *din2;
57     return ret_val;
58 } /* dlaisnan_ */
59