A possibility is that 10&#: and (,10)&#: could have different results.
On Thursday, July 5, 2018, 10:57:37 a.m. EDT, Henry Rich
<[email protected]> wrote:
I have been wondering, if this simple idea is so good, why didn't Ken
think of it?
I think I have the answer.
With the new definition, we would have
10 #: 123 1230 1234
1 2 3 0
1 2 3 0
1 2 3 4
because of left-justification of assembled results. (Note that #: y is
defined with infinite rank to avoid this problem; I think it is out of
the question to change the rank of x #: y, for compatibility reasons)
Results on lists would have this peculiarity. And, #. would be an
imperfect inverse for #: .
So I think rather than having this odd behavior Ken forced us to use
#.^:_1, which DOES have infinite rank and even right-justifies properly:
10 #.^:_1 ] 123 1234
0 1 2 3
1 2 3 4
[20 years of using J and 2 years of intimate work with the source code,
and there are still these gems of Roger's that surprise me.]
For all that, I think I would support making the change Joey suggests,
but I would want more time for all of us to think it over.
Henry Rich
On 7/4/2018 1:37 AM, Joey K Tuttle wrote:
> The proposed change is only to Antibase (#:) not Copy (#)
>
> Plus, all the functionality of #: would be maintained and the statement from
> NuVoc, "x #: y is used only when you need to state how many places you want
> in the result would still remain in effect but the left argument be required
> to be a vector (even if only 1 place was sought).
>
>
>> On 2018Jul 3, at 21:41, Skip Cave <[email protected]> wrote:
>>
>> As long as we don''t change this functionality:
>>
>> 1 1 0 1 0 0 1#10 2 34 13 6 87 9
>>
>> 10 2 13 9
>>
>>
>> Skip Cave
>> Cave Consulting LLC
>>
>>
>> On Tue, Jul 3, 2018 at 11:33 PM Jimmy Gauvin <[email protected]> wrote:
>>
>>> Hi,
>>>
>>> I also support the idea of this scalar extension.
>>>
>>> #.inv or #.^:_1 have a "kludgy" feeling ...
>>>
>>>
>>> Jimmy
>>>
>>> On Tue, Jul 3, 2018 at 11:31 PM, Joey K Tuttle <[email protected]> wrote:
>>>
>>>> Can anyone provide a reason it would be undesirable to have a scalar left
>>>> (x) argument to #: behave any differently than x (#.^:_1) y ?
>>>>
>>>> In NuVoc I find - "
>>>> x #: y is used only when you need to state how many places you want in
>>> the
>>>> result, or if x contains differing values. If you want just sufficient
>>>> places to hold the value of y in the base x, use #.inv to convert to a
>>>> fixed base.
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