[Jprogramming] When a <. _ is less than a

[Thomas Costigliola]

Infinity is a feature of double; extended integers and rationals have no 
notion of infinity so normally arithmetic gets done in double. So if 
your array has numbers that are too large for machine integers the easy 
way out is to convert the extended precision. You could test for special 
cases, e.g., when  <.  has an extended and double argument that only 
contains infinity and return the extended, but that doesn't seem very 
satisfying. I think it requires more thought.

BTW, anyone is welcome to discuss extensions to Unbox by opening a new 
issue: https://github.com/iocane/unbox/issues

If you are not satisfied with that system I am open to suggestions for 
implementing a better one.

On 02/03/2016 02:02 PM, Dan Bron wrote:
> I know we have yet to organize a formal process for building and disseminating a community-driven implementation of J, but in anticipation of that day’s arrival, perhaps we can start collecting community-driven proposals for enhancements?
>
> One such enhancement could be special code that detects whether the argument to an arithmetic dyad is the scalar _ (or __ or _.) and if so, avoids demoting the other argument to double if it’s already extended or rational.
>
> I have other ideas too. But maybe we should collect them on the Wiki?
>
> -Dan
>
>
>> On Feb 2, 2016, at 9:12 PM, Henry Rich <HenryHRich at gmail.com> wrote:
>>
>> No, extendeds promote to float on mixed operations.
>>
>> Henry Rich
>>
>> On 2/2/2016 9:09 PM, 'Pascal Jasmin' via Programming wrote:
>>>     9223372036854736345 <. _
>>> 9.22337e18
>>>
>>> result is a double.  <. double is the closest integer it can find.
>>>
>>> this seems like a problem though:
>>>
>>>
>>>      9223372036854736345x <. _
>>> 9.22337e18
>>>
>>>
>>>
>>> ----- Original Message -----
>>> From: Henry Rich <henryhrich at gmail.com>
>>> To: Programming forum <programming at jsoftware.com>
>>> Sent: Tuesday, February 2, 2016 9:05 PM
>>> Subject: [Jprogramming] When a <. _ is less than a
>>>
>>> I'm stepping up to the world of 64-bit integers, and stepping into cowflops.
>>>
>>> This took me quite a while:
>>>
>>>       <. 9223372036854736345 <. _
>>>
>>> 9223372036854735872
>>>
>>>
>>> See that?  Take the minimum of (number) and (infinity), and the result
>>> is less than (number)!
>>>
>>> Yes, I understand why it happens.  Now I do.  Be warned.
>>>
>>> Henry Rich
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