It probably would be nice to have something like an ML-flavored compiler
for some subset of J.

J already lets you link to freshly built shared objects (also known as
"DLLs") using 15!: so all the next step is probably for someone to build a
suitably small example implementation.

There's actually a huge variety of such tools. They accumulate faster than
most people can study them. Fortunately, no one needs to use most of their
features - especially for starting projects.

Thanks,

-- 
Raul

On Mon, Aug 4, 2014 at 3:30 PM, Alex Giannakopoulos <[email protected]
> wrote:

> Hm, interesting approach, that of Roger's, I still haven't digested it all,
> but sometimes it would be nice to be able to tackle these problems the same
> as everybody else in the world...
>
>
> On 4 August 2014 20:12, Alex Giannakopoulos <[email protected]>
> wrote:
>
> > I used the following memoized code,
> >
> > nextcol =: 3 : 0
> >
> > if. 0=2|y do. -: y
> >
> > else. >: 3*y
> >
> > end.
> >
> > )
> >
> >
> > colchain =: 3 : 0 M.
> >
> > if. y=2 do. 1,2
> >
> > else. chain=. colchain nextcol y
> >
> > (>:0{chain),x:y>.1{chain
> >
> > end.
> >
> > )
> >
> > but it took forever to generate the following I aborted it.
> >    colchain"0 (2}.i.1000001)
> >
> > I wonder if I did something wrong.
> > It seems to work if, for instance, you give
> >    colchain"0 (2+i.9999)
> > Which makes me think the memoization isn't working
> > Even my slow Scheme interpreter gives the answer in 10 seconds or so, C++
> > in less than a second.
> >
> >
> > OTOH, old hands say that J isn't really meant for recursion.  I wonder if
> > this problem should be tackled differently.
> >
> > OK, I'm off to read Roger's post that Dan pointed to...
> >
> >
> >
> > On 4 August 2014 17:30, mvillarino <[email protected]> wrote:
> >
> >> 2014-08-04 14:12 GMT+02:00 Dan Bron <[email protected]>:
> >> > If you're OK with spoilers, have you seen Roger's Collatz Conjecture
> >> essay
> >> > on the Wiki?
> >> >
> >> >      http://jsoftware.com/jwiki/Essays/Collatz%20Conjecture
> >> >
> >>
> >> ? I googled for information on a J spoiler... but no, I haven't found
> it.
> >> Thanks a lot !!!
> >> ----------------------------------------------------------------------
> >> For information about J forums see http://www.jsoftware.com/forums.htm
> >>
> >
> >
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