These are equivalent:
(,+/ @(_2&{.))^:4(1)
1 1 2 3 5
(,+/ @(_2&{.))(,+/ @(_2&{.))(,+/ @(_2&{.))(,+/ @(_2&{.))(1)
1 1 2 3 5
In other words, (F)^:4 does F four times.
Does this help?
Thanks,
--
Raul
On Thu, Mar 2, 2017 at 2:38 PM, Linda A Alvord <[email protected]> wrote:
> Joe, this has taken me a while because I like to understand something, at
> least a little bit, before I respond. I can't quite how this works.
>
> (,+/ @(_2&{.))^:14(1)
> 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610
>
> You get an extra term, but I could define your verb.
>
> fibjb=: 13 :'}:(,[:+/ (_2&{.))^:y 1'
> fibjb 14
> 1 1 2 3 5 8 13 21 34 55 89 144 233 377
>
> But I wish I could understand how it works as it looks so simple.
>
> A tree didn't help much:
>
>
> 5!:4 <'fibjb'
> ┌─ 3
> ── : ─┴─ ,:'}:(,[:+/ (_2&{.))^:y 1'
>
> Dissect seemed to withhold its secrets. SO it's up to you to help me.'
>
> load 'debug'
> dissect 'fibjb 14'
>
> Thanks in advance. Linda
>
> -----Original Message-----
> From: Programming [mailto:[email protected]] On Behalf
> Of Joe Bogner
> Sent: Monday, February 27, 2017 9:49 AM
> To: [email protected]
> Subject: Re: [Jprogramming] Explicit fib
>
> This is how I would approach it for young children -- attempting to follow
> your english description
>
> fibJ =: 3 : 0
>
> firstLast =. 1
> secondLast =. 0
> total =. 1
>
> for_N. i. (y-1) do.
>
> term =. (firstLast + secondLast)
> secondLast =. firstLast
> firstLast =. term
>
> total =. total,term
>
> end.
> total
> )
> fibJ 15
> 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610
>
> The definition is simpler if you just want the Nth number
>
> fibJ =: 3 : 0
>
> firstLast =. 1
> secondLast =. 0
>
> for_N. i. (y-1) do.
>
> term =. (firstLast + secondLast)
> secondLast =. firstLast
> firstLast =. term
> end.
> term
> )
> fibJ 15
> 610
>
>
>
> On Mon, Feb 27, 2017 at 9:16 AM, David Lambert <[email protected]> wrote:
>> fib3=: 13 :'}.1|.,''),(fib2 '',"_ 1":i.y,1'
>>
>> ". fib3 6
>> 0 1 1 2 3 5
>>
>>
>> Let's reorganize by grouping all the strings to increase the sentence
>> legibility.
>>
>> '),(fib2 ' ,"_ 1 ": ,. i. 7
>> ),(fib2 0
>> ),(fib2 1
>> ),(fib2 2
>> ),(fib2 3
>> ),(fib2 4
>> ),(fib2 5
>> ),(fib2 6
>>
>> From here ravel, rotate by one position, finally discard the extra comma.
>>
>>
>> On 02/27/2017 07:00 AM, [email protected] wrote:
>>>
>>> Date: Mon, 27 Feb 2017 05:01:34 -0500
>>> From: "Linda A Alvord"<[email protected]>
>>> To:<[email protected]>
>>> Subject: Re: [Jprogramming] Explicit fib
>>> Message-ID: <000301d290e0$7ae35ac0$70aa1040$@net>
>>> Content-Type: text/plain; charset="utf-8"
>>>
>>> I like fib2 and things were going well but I hit a snag:
>>>
>>> ]W=:*i.2 2
>>> 0 1
>>> 1 1
>>> mp=:+/ . *
>>> fib2=:3 : '{. W&mp^:y 0 1'
>>> ". }:, (14 5$'(fib2'),"1 (' ',"1 ' ',"1 ":,.>:i.14),"1 '),'
>>> 1 1 2 3 5 8 13 21 34 55 89 144 233 377
>>> fib3=: 13 :' ". }:, ((y,5)$'(fib2'),"1 (' ',"1 ' ',"1
>>> ":,.>:i.y),"1 '),''
>>> |domain error: fib2
>>> | {.W&mp ^:y 0 1
>>> It doesn't like the fact that that the fib2 should still be just
>>> letters.
>>>
>>> It was fun anyway. Linda
>>
>>
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