libm-test.inc: Computing ulps near FP_ZERO.

[Rich Felker]

On Tue, Apr 09, 2013 at 11:39:44AM -0400, Carlos O'Donell wrote:
> On 04/08/2013 10:09 PM, Rich Felker wrote:
> > I'm a bit confused about this whole discussion. If the test is
> > cos(M_PI_2) then according to Wolfram Alpha,
> > cos(1.5707963267948965579989817342720925807952880859375), where that
> > argument is the exact value of M_PI_2, evaluates to approximately:
> > 
> >     6.123233995736765886130329661375001... × 10^-17
> 
> Could you do me a favour and compute:
> 
> cpow (0.75 + 1.25 i, 0.75 + 1.25 i)?

Wolfram Alpha says:

0.11750629391447355542027983221042048264448457971691710227141... +
0.34655274770833867648302535206041800107792019145641861264503... i

(http://www.wolframalpha.com/input/?i=%280.75%2B1.25i%29%5E%280.75%2B1.25i%29)

> Could you also compute:
> 
> cosf(M_PI_2)?

M_PI_2 converted to float is: 0x1.921fb6p+0, or as an exact decimal
value, 1.57079637050628662109375

Wolfram Alpha gives:

-4.371139000186241438857289400265215231661253217515547583... × 10^-8

(http://www.wolframalpha.com/input/?i=cos%281.57079637050628662109375%29)

Rich