ts'~.;<@(*{.)\.>:i.1000'
0.0072987262 14949888
ts'~.,*/~>:i.1000'
0.011011744 26233600
(~.,*/~>:i.1000)-:~.;<@(*{.)\.>:i.1000
1
R.E. Boss
> -----Oorspronkelijk bericht-----
> Van: programming-boun...@jsoftware.com
> [mailto:programming-boun...@jsoftware.com] Namens R.E. Boss
> Verzonden: maandag 25 juni 2012 18:57
> Aan: 'Programming forum'
> Onderwerp: Re: [Jprogramming] Multiplying with folds
>
>
> ;<@(*{.)\.>:i.5
> 1 2 3 4 5 4 6 8 10 9 12 15 16 20 25
>
>
> ~.,*/~>:i.5
> 1 2 3 4 5 6 8 10 9 12 15 16 20 25
>
>
> R.E. Boss
>
>
> > -----Oorspronkelijk bericht-----
> > Van: programming-boun...@jsoftware.com
> > [mailto:programming-boun...@jsoftware.com] Namens Raul Miller
> > Verzonden: maandag 25 juni 2012 18:51
> > Aan: Programming forum
> > Onderwerp: Re: [Jprogramming] Multiplying with folds
> >
> > Why do you want this?
> >
> > If it's efficiency, note that the size of the dense array */~N is
> > typically less than the size of a linked list which only represents
> > the products of unique combinations of pairs (if we assume that linked
> > list pointer size is approximately the same size as a number), and
> > also note that typical cpu cache implementation heavily favors regular
> > operations.
> >
> > If it's because you need unique values, you might consider using:
> >
> > ~.,*/N
> >
> > If it's for some other purpose, the topic might have inherent interest...
> >
> > Thanks,
> >
> > --
> > Raul
> >
> > On Mon, Jun 25, 2012 at 12:37 PM, David Vaughan <purpleblue...@gmail.com>
> > wrote:
> > > I'm looking for a verb to achieve the same thing as just the unique items
> > > of */~ N, i.e. n0*(n0 ... nk) n1*(n1 ... nk) n2*(n2 ... nk) ... nk*nk.
> > >
> > > I can easily create the result, but I want to be able to calculate it more
> > > efficiently, without having to do the multiplications that will ultimately
> > > be redundant (which would be ~.,*/~ N).
> > >
> > > I'm not particularly good with folds and similar concepts, so I expect the
> > > solution is relatively simple. Can anyone help?
> > >
> > > Many thanks.
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