> From: "Sherlock, Ric" <[EMAIL PROTECTED]>
>
> ---Raul Miller wrote:
> > Was there anything wrong with my definition for join?
> > join=: [EMAIL PROTECTED] }. [:;,L:0
>
> It's nice and simple,
> join03=: [EMAIL PROTECTED] }. [:;,&.>
> Is perhaps slightly clearer and a little faster, but doesn't handle left args
> of
> length >1.
> join04 / join05 seem to have the best combination of performance and
> features,
> but are not as simple or easy to understand.
>
> a=: '-'
> b=: 100000 [EMAIL PROTECTED] 8
> c=: (b&(<@{."0 _)) 'abcdefghi'
>
> ts=: 6!:2 , 7!:[EMAIL PROTECTED]
>
> join01=: [: ; [EMAIL PROTECTED] , [: , [EMAIL PROTECTED] ,. [EMAIL PROTECTED]
>
> join02=: [EMAIL PROTECTED] }. [:;,L:0
> join03=: [EMAIL PROTECTED] }. [:;,&.> NB. Use each instead of L:0
>
> join04=: ' '&$. :(4 : '(;@(#^:_1!.(
> join05=: 3 : 0 NB. Explicit version of join04
> ' ' join04 y
> :
> (;@(#^:_1!.(
> )
>
> 50{.a join01 c
> ab-abcd-abcd-abc-ab--ab-abcde-abcde--abc-a-abcd--a
>
> *./(
> 1
>
> 20 ts 'a join01 c'
> 0.143952 2.91738e6
>
> 20 ts 'a join02 c'
> 0.0392969 7.8592e6
>
> 20 ts 'a join03 c'
> 0.0339473 7.85914e6
>
> 20 ts 'a join04 c'
> 0.0361777 1.83859e6
>
> 20 ts 'a join05 c'
> 0.0353627 1.83859e6
Here's one that is similar in time and space to 04 and 05,
but is very simple to understand.
join08=: [EMAIL PROTECTED] }. [EMAIL PROTECTED] ;@,. ]
20 ts 'a join08 c'
0.0295858 1.98349e6
20 ts 'a join05 c'
0.0272022 1.83859e6
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