you meant this:
0 ?@:($&>~) i.4
don't actually understand why ?@ is different though.
----- Original Message -----
From: Raul Miller <rauldmil...@gmail.com>
To: Programming forum <programm...@jsoftware.com>
Sent: Thursday, July 7, 2016 11:25 AM
Subject: Re: [Jprogramming] Use of (@) 'Atop'
(In case this is not obvious, I should note that you will need to add
a pair of parenthesis to that example before the actual difference
shows up.)
--
Raul
On Thu, Jul 7, 2016 at 11:23 AM, Raul Miller <rauldmil...@gmail.com> wrote:
> 0 ?@$&>~ i.4
>
> Does that help?
>
> Thanks,
>
> --
> Raul
>
>
> On Thu, Jul 7, 2016 at 10:06 AM, 'Pascal Jasmin' via Programming
> <programm...@jsoftware.com> wrote:
>> I'd like to see an example.
>>
>>
>>
>>
>> ----- Original Message -----
>> From: Raul Miller <rauldmil...@gmail.com>
>> To: Programming forum <programm...@jsoftware.com>
>> Sent: Thursday, July 7, 2016 9:59 AM
>> Subject: Re: [Jprogramming] Use of (@) 'Atop'
>>
>> Only for this example.
>>
>> I can construct other examples where ?@ and ?@: give different results.
>>
>> Do you see why?
>>
>> Thanks,
>>
>> --
>> Raul
>>
>>
>> On Thu, Jul 7, 2016 at 9:35 AM, 'Pascal Jasmin' via Programming
>> <programm...@jsoftware.com> wrote:
>>> ? (2,y) $ 0 or u N v N
>>>
>>>
>>> is more formally equivalent to
>>>
>>>
>>> (2,y)?@:$ 0 or N u@:v N
>>>
>>>
>>> but because ? is a rank 0 verb, ?@ and ?@: will always give the same result.
>>>
>>>
>>>
>>>
>>> ----- Original Message -----
>>> From: Martin Kreuzer <i...@airkreuzer.com>
>>> To: programm...@jsoftware.com
>>> Sent: Thursday, July 7, 2016 8:37 AM
>>> Subject: [Jprogramming] Use of (@) 'Atop'
>>>
>>> Hi all -
>>>
>>> Approximating Pi using the Monte Carlo method (circle enscribed in
>>> unit square) came up with
>>>
>>> pia=. 13 : '(4 * y %~ +/ 1 >: +/ *: <: +: ? (2,y) $ 0)'("0)
>>> (pia 10^(4+i.3)) ,:(4+i.3)
>>> 3.1524 3.1438 3.14106
>>> 4 5 6
>>>
>>> I then compared my version with the J verb at Rosetta Code and the
>>> only difference I found was the use of 'Atop':
>>>
>>> piMC=: monad define "0
>>> 4* y%~ +/ 1>: %: +/ *: <: +: (2,y) ?@$ 0
>>> )
>>>
>>> Q:
>>> What is the advantage (in this particular case) of using 'Atop'..?
>>> ? (2,y) $ 0
>>> vs
>>> (2,y) ?@$ 0
>>>
>>> Thanks
>>> -M
>>>
>>> ----------------------------------------------------------------------
>>> 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
