Re: Detect negative zero (was Re: Infinity as index)

["Liam Devine" <liamdevine@...>]

On 24/04/14 19:22, Doug Currie wrote:
>>
>> On 24/04/14 17:15, Dirk Laurie wrote:
>>>
>>> The hardest test of all is to distinguish between 0 and -0.
>>> If you can improve on the following, please post.
>>>
>>> if x==0 and 1/x>0 then -- x is 0
>>> if x==0 and 1/x<0 then -- x is -0
>>
> 
> You can get by without the and:
> 
>> function is_minuszero (x) return 1/x == -1/0 end
>> function is_pluszero (x) return 1/x == 1/0 end
> 
> e
> 

The problem with both of these methods is you have just fired signals
for which the host could have set traps.


-- 
Liam

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