[Jprogramming] Performance question

[Ben Gorte]

Furthermore:

spacetimex =: 7!:2 , 6!:2@]

spacetimex 'a=: 1 (2 3 4}) a'

1408 1.9e_5

spacetimex 'b=: 1 (2 3 4}) b'

1408 1.9e_5


(this looks okay, but can't explain)




On Thu, 21 Oct 2021 at 21:11, Ben Gorte <bgorte at gmail.com> wrote:

> I thought I might know the answer, but it appears I do not.
> However, I noticed that they are equally fast when I use 6!:2 alone:
>
>
> (1000) 6!:2 'a=:1 (2 3 4) } a'
>
> 2.378e_6
>
> (1000) 6!:2 'b=:1 (2 3 4) } b'
>
> 2.316e_6
>
>
> Also, with:
>
> spacespacex =: 7!:2 , 7!:2@] NB. why?
>
> you get:
>
> spacespacex 'a=:1 (2 3 4)}a'
>
> 1050080 1408
>
> spacespacex 'b=:1 (2 3 4)}b'
>
> 1073743328 1408
>
>
> Is this a clue?
>
>
> Ben
>
>
>
>
> On Thu, 21 Oct 2021 at 19:19, Elijah Stone <elronnd at elronnd.net> wrote:
>
>>     a=: 1e6$0
>>     b=: 1e9$0
>>     timespacex 'a=: 1 (2 3 4}) a'
>> 0.000395 1408
>>     timespacex 'b=: 1 (2 3 4}) b'
>> 0.26758 1408
>>
>> Since both of these operations take up the same amount of space, I assume
>> they are done in-place.  But if that is the case, why does the latter
>> take
>> longer?
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>