Thanks for replying, everyone.Sorry the formatting was all garbled. It was copy
and pasted.
It seems, for me at least, that
>./ @ q:
is the simplest and most elegant way to do it. I'm still struggling with the @
and & purposes, but I think only reading the explanations more carefully can
fix that.
Regards,Jon
> From: rauldmil...@gmail.com
> Date: Wed, 26 Feb 2014 09:49:25 -0500
> To: programm...@jsoftware.com
> Subject: Re: [Jprogramming] Finding Largest Prime of Numbers (Tacit)
>
> When I want to see inside the execution of a tacit verb, I usually
> introduce verbs that let me see or grab values.
>
> For example:
> (#~ [:(e. p:)+/\@:=&' ')'this is an example of something'
> an example something
>
> So here's a couple verbs, to see values and to grab them:
>
> see=: 1!:2&2
> grab=: 3 :'KEEP=:y'
>
> And here's how they might look in action:
>
> (#~ [:see@(e. grab@p:)+/\@:=&' ')'this is an example of something'
> 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 0 0 0 1 1 1 1 1 1 1 1 1 1
> an example something
>
> KEEP
> 13
>
> Obviously there are limits to this technique, so it requires a little
> thought and you especially need to think about rank. That's not
> entirely a bad thing.
>
> (#~ [:see@(e. grab@:p:)+/\@:=&' ')'this is an example of something'
>
> What do you think KEEP looks like this time?
>
> Thanks,
>
> --
> Raul
>
>
> On Wed, Feb 26, 2014 at 3:03 AM, Linda Alvord <lindaalv...@verizon.net> wrote:
> > Trace has a problem. It works fine with an explicit statement.
> >
> > require'trace'
> > trace 'f=:{: 3 p: 23434'
> > --------------- 2 Dyad -------
> > 3
> > p:
> > 23434
> > 2 11717
> > --------------- 0 Monad ------
> > {:
> > 2 11717
> > 11717
> > --------------- 7 Is ---------
> > f
> > =:
> > 11717
> > 11717
> > ==============================
> > 11717
> >
> > This is ok. Now try the tacit expression.
> >
> > f 23434
> > 11717
> > f
> > [: {: 3 p: ]
> >
> >
> > trace 'g=:[: {: 3 p: 23434'
> > --------------- 2 Dyad -------
> > 3
> > p:
> > 23434
> > 2 11717
> > --------------- 1 Monad ------
> > {:
> > 2 11717
> > 11717
> > --------------- 0 Monad ------
> > [:
> > 11717
> > |domain error: executet
> > | t_z=. ([:)(11717)
> >
> >
> > Is trace not appropriate for tacit verbs?
> >
> > Linda
> >
> > -----Original Message-----
> > From: programming-boun...@forums.jsoftware.com
> > [mailto:programming-boun...@forums.jsoftware.com] On Behalf Of David Lambert
> > Sent: Tuesday, February 25, 2014 1:13 AM
> > To: programming
> > Subject: Re: [Jprogramming] Finding Largest Prime of Numbers (Tacit)
> >
> > j is a multiple instruction single data language and has many many ways
> > to pass data, including as far as I can tell all combinations of
> > monadic, dyadic verbs considering single verbs, their obverses where
> > practical, the trains of even numbers of verbs, and of odd numbers of
> > verbs with more than two verbs. Trains have infinite rank, that's why
> > we cannot consider a single verb as a train. The train/rank question
> > often appears first with table. (Usually) use the train atomically, at
> > rank 0 .
> >
> > X train"0/ Y
> >
> > Assigning a list of verbs to a proverbial name is a most surprising
> > aspects of j, one which I didn't realize from the documents for a long
> > long time. Where stated "Substituted as if in parentheses." is an
> > absolutely huge short sentence. Parentheses completely change (what I
> > thought I had as) the sentence. If
> >
> > {: q: 45
> > 5
> >
> > biggest_prime_factor_wrong =: {: q:
> >
> > biggest_prime_factor_wrong 45
> > |domain error: biggest_prime_factor_wrong
> > | biggest_prime_factor_wrong 45
> >
> > biggest_prime_factor_wrong is a hook with hook data passing. {: doesn't
> > have a dyadic definition. Hence the domain error of
> > ({: q:) 45 NB. equivalent to 45 {: q: 45
> >
> > As far as I can tell, cap in a fork effectively means to use the monadic
> > definition of the verb immediately to that cap's right.
> >
> > biggest_prime_factor =: [: {: q:
> >
> > biggest_prime_factor 45
> > 5
> >
> > Other choices. Of those that are correct for a purpose the performance
> > can drastically vary. Use the largest chunks possible to keep j from
> > devoting resources to checking data types, frames, and item rank.
> > Conjunctions here bind first, and from left to right form verbs:
> >
> > {:@q: 45
> > 5
> > {:@:q: 45
> > 5
> > {:&q: 45
> > 5
> > {:&:q: 45
> > 5
> >
> > I've personally chosen to write verbs tacitly in the interpreter session
> > with parentheses, using under, at, atop, compose, or appose when I can
> > so that I can directly create proverbs. Having little faith in the
> > future ordering of prime factors, I'd use bpf =: ([: >./ q:) ,
> > emphasizing the train with parentheses.
> >
> > Stick with j though it may take years, and please pounce on my errors,
> > David Lambert
> > ----------------------------------------------------------------------
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> >
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