You are free to move on.

You do not have to change J (and, thus, making it harder to learn)
when you do so.

That said, no one has silenced *you* - you are currently posting more
here than everyone else combined. If anyone is being silenced, it's
others here on the forums.

Thanks,

-- 
Raul




On Sun, Oct 15, 2017 at 10:37 AM, Erling Hellenäs
<[email protected]> wrote:
> Hi all !
>
> I don't think we should turn down change requests because the requester does
> not have the same qualifications as Ken Iverson. I think we should have a
> factual discussion about the requests in which the qualified people we have
> available today participate. I think we have to  accept that Ken Iverson is
> no more alive and that we have to move on without him. We have a lot of
> qualified people in our maillists. If we don't silence them by attacking
> them as soon as they say something, we are well qualified to take decisions
> and move on.
>
> Cheers,
>
> Erling Hellenäs
>
>
> On 2017-10-14 21:19, Don Guinn wrote:
>>
>> I think we have had a factual discussion on the molulo problem. We just
>> haven't found a good solution to the problem. Larger precision only moves
>> the problem. It does not fix it. None of the possible solutions presented
>> so far seem satisfactory because there are so many ways for them to fail
>> anyway, if it is assumed that coming up with a residue of zero is really
>> wrong when the numbers presented to residue exceed known precision limits.
>>
>> We learned several good things in this exercise. One, the square root of
>> an
>> integer perfect square stays integer. Two, we can't count on conversion of
>> integer to float to be exact. Three, solutions to problems must be
>> realistic. There will almost always be compromises and tradeoffs. We must
>> watch answers we get as was done by whoever asked the question in the
>> first
>> place. That he asked the question is most important. It now makes us all
>> aware of some possible problems we can get into when pushing the limits of
>> the hardware and software.
>>
>> As to spinoffs. It is great for people to explore alternative solutions to
>> programming language problems, whether J, C or any other language. But
>> they
>> are explorations. That doesn't mean that they will stand for the test of
>> time. Ken and many others spent a lot of careful designing J. It is
>> important to fully understand their work before trying to "improve" on
>> what
>> they did.
>>
>> On Sat, Oct 14, 2017 at 12:32 PM, Erling Hellenäs
>> <[email protected]>
>> wrote:
>>
>>> Hi all !
>>>
>>> I think all problems should be put into the bugtracker and that there
>>> should be factual discussions about how to solve them, so that, should
>>> anyone want to finance or merge a solution, they can do so.
>>> If we deny that any problems exist there will be no development.
>>> If we turn all requests for change down there will be no development.
>>> People are cloning J and are willing to supply their patches for free. If
>>> we don't cooperate with them there will be no development.
>>>
>>> Cheers,
>>>
>>> Erling Hellenäs
>>>
>>>
>>>
>>>
>>> On 2017-10-14 19:14, Don Guinn wrote:
>>>
>>>> I think that you are making this out to be a big problem. I don't think
>>>> it
>>>> is. We have much bigger problems with coming up with good solutions to
>>>> problems. Scaling is one of the biggest. That J deals with numbers as
>>>> numbers, not as integer or float or whatever and does not predefine
>>>> limits
>>>> on array sizes removes many of the problems found in traditional
>>>> programming languages. At the same time it generates other problems like
>>>> double float cannot represent all 64 bit integers resulting in loss of
>>>> precision with automatic conversion of integer to float.
>>>>
>>>> Whether the benefits of J's approach outweigh the disadvantages depends
>>>> on
>>>> whom you ask. But possible solutions like those you suggested are only
>>>> partial solutions. We need to watch for things that don't make sense,
>>>> whether caused by our design, or the design of the programming language.
>>>> They all have lots of gotchas.
>>>>
>>>> On Sat, Oct 14, 2017 at 9:11 AM, Erling Hellenäs <
>>>> [email protected]>
>>>> wrote:
>>>>
>>>> Hi all!
>>>>>
>>>>> We now have an additional proposed solution from Raul, using extended
>>>>> precision and rationals instead of integers.
>>>>>
>>>>> Any more proposed solutions?
>>>>>
>>>>> Opinions about the proposed solutions?
>>>>>
>>>>> Cheers,
>>>>>
>>>>> Erling Hellenäs
>>>>>
>>>>>
>>>>>
>>>>> On 2017-10-13 22:28, Erling Hellenäs wrote:
>>>>>
>>>>> Hi all!
>>>>>>
>>>>>> You moved to 64 bit integer. You can't go back. Now there is a serious
>>>>>> problem? You have to determine how to solve it?
>>>>>> The simple solution is to move to quad precision floats? Is it
>>>>>> possible
>>>>>> to add support for keeping the integers ? The ability to do all
>>>>>> integer
>>>>>> arithmetic on integers? To stop auto-converting to floats? To
>>>>>> internally
>>>>>> work with quad precision floats in integer arithmetics?
>>>>>> Maybe you could add support for the new IEEE decimal standard? Move
>>>>>> integer arithmetic to them?
>>>>>> Are there other solutions?
>>>>>>
>>>>>> Cheers,
>>>>>>
>>>>>> Erling Hellenäs
>>>>>>
>>>>>> On 2017-10-08 16:54, Don Guinn wrote:
>>>>>>
>>>>>> I realize this is stating the obvious, but the loss of precision is
>>>>>> the
>>>>>>>
>>>>>>> result of 64 bit integer support. Previously "upgrading" a number
>>>>>>> from
>>>>>>> integer to float was exact. Though the residue problem for very large
>>>>>>> numbers still existed, at least it didn't involve loss of precision.
>>>>>>>
>>>>>>> It's my personal opinion that one should always be careful when
>>>>>>> working
>>>>>>> around the limits of a system. But what should be done when things go
>>>>>>> a
>>>>>>> little crazy around those limits? It is unfortunate that IEEE only
>>>>>>> implemented indeterminate (_.) when it could have set other flags in
>>>>>>> the
>>>>>>> unused bit configuration to indicate things like underflow, but not
>>>>>>> zero
>>>>>>> or
>>>>>>> overflow but not infinity. But they didn't.
>>>>>>>
>>>>>>> A while back J had an option for upgrade to go to rational instead of
>>>>>>> float. It was useful in labs to more easily show interesting
>>>>>>> properties
>>>>>>> of
>>>>>>> numbers. Is that option still around? If so it could be used in mod
>>>>>>> as
>>>>>>> an
>>>>>>> option. But it cannot be always known that the number will eventually
>>>>>>> be
>>>>>>> used in mod. And many transcendental verbs must go to float.
>>>>>>>
>>>>>>> Current hardware now supports quad precision float, at least some do.
>>>>>>> If
>>>>>>> quad float were used then the loss of precision goes away when
>>>>>>> converting
>>>>>>> 64 bit integer to float. But that doubles the size of float, and even
>>>>>>> though memory is getting huge it's still a concern for big problems.
>>>>>>> Not
>>>>>>> to
>>>>>>> mention that quad float is probably slower than double float. And it
>>>>>>> may
>>>>>>> not be supported on all hardware, similar to the AVX problem.
>>>>>>>
>>>>>>> IBM's PLI has an interesting approach to precision. You told it (in
>>>>>>> decimal
>>>>>>> digits) the largest numbers you will deal with and the number of
>>>>>>> digits
>>>>>>> after the decimal. Then it picked the best way to store the numbers
>>>>>>> given
>>>>>>> available hardware. In J we have 64 bit integers and floats with
>>>>>>> maybe
>>>>>>> 16
>>>>>>> significant decimal digits and a tremendous range for exponents. Most
>>>>>>> problems we deal with don't need such big numbers. An argument many
>>>>>>> use
>>>>>>> against J in that it uses so much memory for small numbers. Perhaps a
>>>>>>> global setting with Foreign Conjunction could give a similar choice
>>>>>>> for
>>>>>>> J.
>>>>>>> I would argue against it saying things like single/double/quad float
>>>>>>> or
>>>>>>> 16/32/64 bit integers, but specify what range and significance is
>>>>>>> need
>>>>>>> and
>>>>>>> let J choose how to handle it. Including totally ignoring it for some
>>>>>>> implementations. Supporting this could make the J engine larger, but
>>>>>>> nobody
>>>>>>> seems too concerned with the monstrous size Qt.
>>>>>>>
>>>>>>> Whatever happened with the idea bouncing around of defining a
>>>>>>> floating
>>>>>>> point of arbitrary size and precision like with extended integers and
>>>>>>> rationals?
>>>>>>>
>>>>>>> And now IEEE has a decimal float standard. Right now it seems that
>>>>>>> only
>>>>>>> IBM
>>>>>>> has implemented it in hardware. But think of all the confusion we see
>>>>>>> when
>>>>>>> decimal numbers like 1.1 are not represented exactly in J.
>>>>>>>
>>>>>>> Maybe I rambled a bit. But this all involves problems when, for one
>>>>>>> reason
>>>>>>> or another, the hardware can't handle needed precision.
>>>>>>>
>>>>>>> ----------------------------------------------------------------------
>>>>>>> For information about J forums see
>>>>>>> http://www.jsoftware.com/forums.htm
>>>>>>>
>>>>>>>
>>>>>> ----------------------------------------------------------------------
>>>>>> For information about J forums see http://www.jsoftware.com/forums.htm
>>>>>>
>>>>>>
>>>>> ----------------------------------------------------------------------
>>>>> For information about J forums see http://www.jsoftware.com/forums.htm
>>>>>
>>>>> ----------------------------------------------------------------------
>>>>
>>>> For information about J forums see http://www.jsoftware.com/forums.htm
>>>>
>>>
>>> ----------------------------------------------------------------------
>>> For information about J forums see http://www.jsoftware.com/forums.htm
>>>
>> ----------------------------------------------------------------------
>> For information about J forums see http://www.jsoftware.com/forums.htm
>
>
>
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
----------------------------------------------------------------------
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