/* -- translated by f2c (version 20100827).
You must link the resulting object file with libf2c:
on Microsoft Windows system, link with libf2c.lib;
on Linux or Unix systems, link with .../path/to/libf2c.a -lm
or, if you install libf2c.a in a standard place, with -lf2c -lm
-- in that order, at the end of the command line, as in
cc *.o -lf2c -lm
Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
http://www.netlib.org/f2c/libf2c.zip
*/
#include "f2c.h"
/* > \brief \b IEEECK
=========== DOCUMENTATION ===========
Online html documentation available at
http://www.netlib.org/lapack/explore-html/
> \htmlonly
> Download IEEECK + dependencies
> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/ieeeck.
f">
> [TGZ]</a>
> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/ieeeck.
f">
> [ZIP]</a>
> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/ieeeck.
f">
> [TXT]</a>
> \endhtmlonly
Definition:
===========
INTEGER FUNCTION IEEECK( ISPEC, ZERO, ONE )
INTEGER ISPEC
REAL ONE, ZERO
> \par Purpose:
=============
>
> \verbatim
>
> IEEECK is called from the ILAENV to verify that Infinity and
> possibly NaN arithmetic is safe (i.e. will not trap).
> \endverbatim
Arguments:
==========
> \param[in] ISPEC
> \verbatim
> ISPEC is INTEGER
> Specifies whether to test just for inifinity arithmetic
> or whether to test for infinity and NaN arithmetic.
> = 0: Verify infinity arithmetic only.
> = 1: Verify infinity and NaN arithmetic.
> \endverbatim
>
> \param[in] ZERO
> \verbatim
> ZERO is REAL
> Must contain the value 0.0
> This is passed to prevent the compiler from optimizing
> away this code.
> \endverbatim
>
> \param[in] ONE
> \verbatim
> ONE is REAL
> Must contain the value 1.0
> This is passed to prevent the compiler from optimizing
> away this code.
>
> RETURN VALUE: INTEGER
> = 0: Arithmetic failed to produce the correct answers
> = 1: Arithmetic produced the correct answers
> \endverbatim
Authors:
========
> \author Univ. of Tennessee
> \author Univ. of California Berkeley
> \author Univ. of Colorado Denver
> \author NAG Ltd.
> \date November 2011
> \ingroup auxOTHERauxiliary
===================================================================== */
integer igraphieeeck_(integer *ispec, real *zero, real *one)
{
/* System generated locals */
integer ret_val;
/* Local variables */
real nan1, nan2, nan3, nan4, nan5, nan6, neginf, posinf, negzro, newzro;
/* -- LAPACK auxiliary routine (version 3.4.0) --
-- LAPACK is a software package provided by Univ. of Tennessee, --
-- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
November 2011
===================================================================== */
ret_val = 1;
posinf = *one / *zero;
if (posinf <= *one) {
ret_val = 0;
return ret_val;
}
neginf = -(*one) / *zero;
if (neginf >= *zero) {
ret_val = 0;
return ret_val;
}
negzro = *one / (neginf + *one);
if (negzro != *zero) {
ret_val = 0;
return ret_val;
}
neginf = *one / negzro;
if (neginf >= *zero) {
ret_val = 0;
return ret_val;
}
newzro = negzro + *zero;
if (newzro != *zero) {
ret_val = 0;
return ret_val;
}
posinf = *one / newzro;
if (posinf <= *one) {
ret_val = 0;
return ret_val;
}
neginf *= posinf;
if (neginf >= *zero) {
ret_val = 0;
return ret_val;
}
posinf *= posinf;
if (posinf <= *one) {
ret_val = 0;
return ret_val;
}
/* Return if we were only asked to check infinity arithmetic */
if (*ispec == 0) {
return ret_val;
}
nan1 = posinf + neginf;
nan2 = posinf / neginf;
nan3 = posinf / posinf;
nan4 = posinf * *zero;
nan5 = neginf * negzro;
nan6 = nan5 * *zero;
if (nan1 == nan1) {
ret_val = 0;
return ret_val;
}
if (nan2 == nan2) {
ret_val = 0;
return ret_val;
}
if (nan3 == nan3) {
ret_val = 0;
return ret_val;
}
if (nan4 == nan4) {
ret_val = 0;
return ret_val;
}
if (nan5 == nan5) {
ret_val = 0;
return ret_val;
}
if (nan6 == nan6) {
ret_val = 0;
return ret_val;
}
return ret_val;
} /* igraphieeeck_ */