[Jprogramming] Gustafson's Unums Revisited

[Erling Hellenäs]

Hi all !

There is another Unum implementation in Julia. 
https://github.com/JuliaComputing/Unums.jl

Is it more or less advanced?

Cheers,

Erling


On 2016-08-18 13:19, roger stokes wrote:
> Thanks for your message.
>
> Different results can be produced at different precisions,
> basically because two numbers which are the same at low precision are
> different at a higher precision.
>
> So I don't think these three tests show that the software is incorrect,
> but they show I need to do more work in defining the tests and
> particularly the starting set given by ssfn. It excludes 2 from the set,
> which was a mistake.
>
> Regards
>
>
> On Thu, Aug 18, 2016 at 10:24 AM, Erling Hellenäs <erling at erlinghellenas.se>
> wrote:
>
>> Hi all !
>>
>> I am in J8.0.4 in 64 bit Windows.*
>> *
>>
>> In Lab 36 I get:
>>
>> (P1_P2 OR TWO OR BIGPOS) = MINUSONE PLUS BIGPOS NB. check this
>>
>> 0
>>
>>
>> HALF = ONE MINUS HALF
>>
>> 0
>>
>>
>> ONE = HALF TIMES TWO NB. not in 3-bit cos TWO=BIGPOS
>>
>> 0
>>
>>
>> These three tests are failing?
>>
>>
>> Cheers,
>>
>>
>> Erling
>>
>>
>>
>>
>> On 2016-08-17 15:32, Raul Miller wrote:
>>
>>> Yes.
>>>
>>>      ({.~ i:&'/');(4!:4 <'is_unum') { 4!:3''
>>>
>>> gives the directory where unum's utils.ijs was loaded from. (And this
>>> can even be done in that same script, after is_unum has been defined.)
>>>
>>> That said, for the long run, it would probably be better to stuff this
>>> in a variable and use it where needed, instead of changing the
>>> directory for the entire session. Changing the directory should be
>>> reserved for code that is supposed to take over the session (or, ok,
>>> labs which are intended to teach the user about changing directory).
>>>
>>> Thanks,
>>>
>>>
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