Unfortunately, Lorenz Koehl wants every item with an odd index,
or with an index equal to -1 modulo n.
So if
[q =. 10?10. NB. 3rd call of 10?10, I think
3 0 7 2 9 1 5 8 4 6
odd q NB. Koehl
0 2 1 8 6
3 nth q NB. Koehl
7 1 4
3 ({:;._3~ ,:~)~ q NB. Henry Rich
7 1 4
3(]#~<:@[=|)q NB. R E Boss
2 5 8
Henry’s method looks pretty minimal!
This doesn’t quite work in the general case, but fwiw, anyway:
_3 {: \ q. NB. !
7 1 4 6
Mike
PS I see you’ve just spotted the difference!
Sent from my iPad
> On 31 Oct 2019, at 18:14, R.E. Boss <[email protected]> wrote:
>
> And minus another one:
>
> 3(]#~<:@[=|)i.8
> 2 5
>
>
> R.E. Boss
>
>
>> -----Oorspronkelijk bericht-----
>> Van: Programming <[email protected]>
>> Namens Raul Miller
>> Verzonden: donderdag 31 oktober 2019 18:27
>> Aan: Programming forum <[email protected]>
>> Onderwerp: Re: [Jprogramming] odds and nths
>>
>> One character shorter:
>>
>> 3(]#~0=(|#\))i.8
>> 2 5
>>
>> Thanks,
>>
>> --
>> Raul
>>
>>> On Thu, Oct 31, 2019 at 12:43 PM Henry Rich <[email protected]> wrote:
>>>
>>> 3 ({:;._3~ ,:~)~ i. 8
>>> 2 5
>>>
>>> Henry Rich
>>>
>>>> On 10/31/2019 12:33 PM, Lorenz Köhl wrote:
>>>> NB. get items with odd index
>>>> odd=. ] #~ 0 1 $~ #
>>>>
>>>> Generalizing this I got
>>>>
>>>> NB. get the nth items
>>>> nth=. ] #~ (1 ,~ 0 $~ 1 -~ [) $~ [: # ]
>>>>
>>>> I bet this is not the shortest version!
>>>>
>>>> I tried infix but it includes fret/fill
>>>>
>>>> wrong_odd=. [: {: [: |: _2 ]\ ]
>>>>
>>>> happy halloween
>>>>
>>>> Lo
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>>>
>>>
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