[Jprogramming] Overflow, underflow, floats

[Erling Hellenäs]

Hi all !

As I see it letting calculations with _ and __ return a zero means you 
risk getting random results. I question if this is really an improvement.

If you can not force an exception instead of a loss of precision you 
risk getting random results? These exceptions are a compulsory part of 
the standard for a reason?

Cheers,

Erling


Den 2017-09-20 kl. 23:22, skrev Henry Rich:
> No; see
>
> http://code.jsoftware.com/wiki/Vocabulary/under  Details
>
> http://code.jsoftware.com/wiki/Vocabulary/percent#dyadic   Details
>
> It would perhaps be better if 0 * _5 gave -0, but it doesn't.  The other
> deviations are improvements added by J.
>
> Henry Rich
>
> On Wed, Sep 20, 2017 at 10:51 AM, Erling Hellenäs <erling at erlinghellenas.se>
> wrote:
>
>> Hi all !
>>
>> Here is part of the standard. Required exception handling. Things I
>> discuss in my post. Is it implemented in J? https://en.wikipedia.org/wiki/
>> IEEE_754#Exception_handling
>> The floating point standard is obviously used in environments where the
>> users can not afford random results, so there must be solutions to the
>> problems I mention, which we also can see in this wikipedia article.
>>
>> Cheers,
>> Erling
>>
>>
>> Den 2017-09-20 kl. 16:27, skrev Erling Hellenäs:
>>
>>> I hope others want to read my post even if Raul discards it as not worthy
>>> of comments. /Erling
>>>
>>>
>>> Den 2017-09-20 kl. 12:25, skrev Raul Miller:
>>>
>>>> This isn't just J - this is the IEEE-754 floating point standard.
>>>>
>>>> It would be really nice if computers could deal with infinities,
>>>> instantly, at no cost. Sadly, though, that's not going to happen.
>>>>
>>>> FYI,
>>>>
>>>>
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