For a little more color: previous discussion:
http://www.jsoftware.com/pipermail/programming/2014-March/035994.html

I'm going to switch back to using i. for this



On Tue, Jan 10, 2017 at 6:15 PM, Joe Bogner <[email protected]> wrote:

> Looks like it is due to the boxing. Please disregard
>
> http://code.jsoftware.com/wiki/Vocabulary/comma#dyadic mentions that
> append in place special code does not work for boxes
>
> f4 =: 3 : 0
>
> a=:a:
>
> for_n. (i. y) do. a=:a,(<n) end.
>
> )
>
>
> (6!:2) 'f4 100'
>
> 0.000336555
>
> (6!:2) 'f4 1000'
>
> 0.0149772
>
> (6!:2) 'f4 10000'
>
> 0.667025
>
> (6!:2) 'f4 20000'
>
> 2.69115
>
> (6!:2) 'f4 100000'
>
> 170.261
>
>
>
>
> On Tue, Jan 10, 2017 at 5:26 PM, Joe Bogner <[email protected]> wrote:
>
>> Why are these so different in execution speed? I'm surprised assembling
>> that linking boxes makes that much of a difference over an number. I need
>> it to be boxed because I'm going to something more complex with each
>> iteration.
>>
>> f1 =: 3 : '(>: each)^:(<y) (<0)'
>>
>>    (6!:2) 'f1 100'
>> 6.01622e_5
>>    (6!:2) 'f1 1000'
>> 0.0012719
>>    (6!:2) 'f1 10000'
>> 0.145702
>>    (6!:2) 'f1 100000'
>> 33.0624
>>
>> f2 =: 3 : '(>:)^:(<y) (0)'
>>
>>    (6!:2) 'f2 100'
>> 4.24675e_5
>>    (6!:2) 'f2 1000'
>> 0.000189688
>>    (6!:2) 'f2 10000'
>> 0.00180487
>>    (6!:2) 'f2 100000'
>> 0.0256836
>>
>>
>> I'm thinking of using ^: to execute something N times with an increasing
>> argument.
>>
>> I could use i. but wanted to try something different
>>
>>
>> JVERSION
>>
>> Engine: j805/j64/windows
>>
>> Release: commercial/2016-12-11T08:02:16
>>
>> Library: 8.05.11
>>
>> Qt IDE: 1.5.3s/5.6.2
>>
>> Platform: Win 64
>>
>> Installer: J805 install
>>
>> InstallPath: c:/program files/j64-805
>>
>> Contact: www.jsoftware.com
>>
>
>
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