Thanks guys, It just goes to show there is always more than one way to
skin a cat!
I am using it on a few thousand items so the speed up is greatly appreciated.
ts=: 6!:2, 7!:[EMAIL PROTECTED]
ts 'pair6a 4000'
0.330374 1.3422e8
ts 'pairi 4000'
11.4952 4.02654e8
Does anyone know why there is a limit error for pair6a 10000 but not
when inside ts? Is there a way to use ts and get it to spit the answer
out?
ts 'pair6a 10000'
2.03573 1.07374e9
pair6a 10000
|limit error
On Fri, Nov 7, 2008 at 7:14 PM, Roger Hui <[EMAIL PROTECTED]> wrote:
> My favorite solution is Arie Groeneveld's pair3, but there
> is a faster and leaner solution:
>
> pair6a=: 3 : 0
> t=. ((2!y),2)$0 1+0
> t=. (1,.-.(-i.)y-2) (}:+/\(-i.)y-1)}t
> +/\t
> )
>
> pair3=:[:;<@({.,.}.)[EMAIL PROTECTED]
>
> (pair3 -: pair6a) 1000
> 1
> ts=: 6!:2 , 7!:[EMAIL PROTECTED]
>
> 10 ts 'pair3 1000'
> 0.0356751 9.63603e6
> 10 ts 'pair6a 1000'
> 0.0190992 8.39136e6
>
> Also, pair6a 1 gives a wrong answer.
>
>
>
> ----- Original Message -----
> From: Devon McCormick <[EMAIL PROTECTED]>
> Date: Friday, November 7, 2008 7:56
> Subject: Re: [Jprogramming] pairs
> To: Programming forum <[email protected]>
>
>> My timings agree with the ones on your clean system: "pair3" is
>> fastest,followed by "pair2", then by "2&comb3"; all three are
>> pretty close to each
>> other and are much faster than the original "pairi":
>>
>> rnk2 100&ts&>'pairi y';'pair2 y';'2&comb3 y';'pair3
>> y' [ y=. 1000
>> 3 29.78 2.61 0.484 2.517e7
>> 1 1.17 1.00 0.019 9.640e6
>> 2 1.20 1.00 0.020 9.636e6
>> 0 1.00 1.00 0.016 9.636e6
>>
>> On Fri, Nov 7, 2008 at 10:28 AM, R.E. Boss
>> <[EMAIL PROTECTED]> wrote:
>>
>> > On a cleaner system I get
>> >
>> > rnk2 5&ts&>'pair2 y';'2&comb3 y';'pair3 y'[y=.5000
>> > 1 1.04 1.00 0.737 2.834e8
>> > 2 1.11 1.00 0.791 2.833e8
>> > 0 1.00 1.00 0.711 2.833e8
>> >
>> > rnk2=: 1 7j2 5j2 10j3 8j_3 ": (,.~[: (/:@/:@:({."1) ,. }."1) (%"1
>> > <./)@:(,.~
>> > */"1))
>> NB. wrap around!
>> >
>> >
>> > R.E. Boss
>> >
>> >
>> > -----Oorspronkelijk bericht-----
>> > Van: [EMAIL PROTECTED]
>> > [mailto:[EMAIL PROTECTED] Namens Arie Groeneveld
>> > Verzonden: vrijdag 7 november 2008 16:25
>> > Aan: Programming forum
>> > Onderwerp: Re: [Jprogramming] pairs
>> >
>> > I executed both lines, having different arguments, several times,
>> > because I didn't get the same result as RE.Boss timings.
>> >
>> > 5j2": (%"1<./) 5&(6!:2)&>'pairi ry';'pair2
>> ry';'2&comb3 ry'[ry=.1000
>> > 34.34 1.00 1.04
>> >
>> >
>> > Devon McCormick schreef:
>> > > This looks like the usual variability of timing few
>> iterations. If you
>> > try
>> > > this with 100 iterations, i.e.
>> > >
>> > > 5j2": (%"1<./) 100&(6!:2)&>'pair2
>> ry';'pair3 ry' [ry=.25
>> > >
>> > > your results should be more stable.
>> > >
>> > > On Fri, Nov 7, 2008 at 9:38 AM, Arie Groeneveld
>> <[EMAIL PROTECTED]>> wrote:
>> > >
>> > >
>> > >> However....
>> > >>
>> > >> Executing the following two lines several times (sometimes
>> I get erratic
>> > >> results):
>> > >>
>> > >> 5j2": (%"1<./) 5&(6!:2)&>'pair2 ry';'pair3
>> ry' [ry=.25
>> > >> 1.00 1.34
>> > >>
>> > >> 5j2": (%"1<./) 5&(6!:2)&>'pair2 ry';'pair3
>> ry' [ry=.1000
>> > >> 1.02 1.00
>> > >>
>> > >>
>> > >> Arie Groeneveld schreef:
>> > >>
>> > >>> Slower , but more concise
>> > >>>
>> > >>> pair3=:[:;<@({.,.}.)[EMAIL PROTECTED]
>> > >>>
>> > >>>
>> > >>> Arie Groeneveld schreef:
>> > >>>
>> > >>>
>> > >>>> pair2=:([:;],."0 _&.>[:<\.1&+)@i.@<:
>> > >>>>
>> > >>>> (pair2-:pairi) 100
>> > >>>> 1
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