[Jprogramming] @ and @: (atop and at)

[Brian Schott]

Raul,

I know that k and g are not equivalent; they were not meant to be.
Neither are f and g equivalent; they are meant to elucidate execution and
parse ordering, I believe.

But I do not think the bottom-to-top execution order is a coincidence. For
example even for your G execution begins at the bottom of the page with *:
. Oh, wait. Maybe we mean different things when we say "bottom": I mean
bottom of the page, do you mean bottom of the tree or something?

Your G differs from k in that the 13 and 3 forms are different from one
another for G. I did not provide the 13 form for k which would have
required parentheses like the following.

13 : '(% %: - + *:)y'

Your warning regarding the precarious font reproduction is well taken.

Thank you,

On Sun, Jan 24, 2016 at 1:42 PM, Raul Miller <rauldmiller at gmail.com> wrote:

> Note, however, that the "top-to-bottom" aspect is coincidental, and that k
> and g are not equivalent.
>
>    G=: 13 :'%%:-+*:y'
>    5!:4<'G'
>   ┌─ [:
>   ├─ %
> ──┤    ┌─ [:
>   │    ├─ %:
>   └────┤    ┌─ [:
>        │    ├─ -
>        └────┤    ┌─ [:
>             └────┼─ +
>                  └─ *:
>    k 9
> 5.19987e16
>    g 9
> 0j_0.111111
>    G 9
> 0j_0.111111
>
> (And, as usual, I expect that list readers will have to ensure that they're
> using an appropriate (fixed width) font to see the tree displays.  I think
> the line of responsibility for that issue looks approximately like printing
> press tradition -> Knuth -> education system -> Microsoft -> education
> system -> Google.)
>
> FYI,
>
> --
> Raul
>
>
> On Sun, Jan 24, 2016 at 10:02 AM, Brian Schott <schott.brian at gmail.com>
> wrote:
>
> > Linda,
> >
> > Thank you for your f, g, and h examples.
> > Together with Henry's long explanations, they helped me better able to
> > understand the tree form. I think **now** I can see that the order of
> > parsing is from left to right before execution which is from bottom to
> top.
> > I used the fork example tree below to see this as well.
> >
> >    k =: % %: - + *:
> >    5!:4 <'k'
> >   ┌─ %
> >   ├─ %:
> > ──┤    ┌─ -
> >   └────┼─ +
> >        └─ *:
> >
> >    g=: 13 :'%@%:@- at +@*:y'
> >    5!:4 <'g'
> >                         ┌─ %
> >                   ┌─ @ ─┴─ %:
> >             ┌─ @ ─┴─ -
> >       ┌─ @ ─┴─ +
> > ── @ ─┴─ *:
> >
> > Now compare the trees of g and k above. (For purposes of comparison, the
> > defined k was constructed with the same order of verbs as the defined g.)
> >
> > Both the definitions of g and k are unadorned with parentheses and both
> are
> > executed from bottom to top in their respective trees. But whereas g's
> tree
> > is upward sloping, k's is downward sloping and the right to left parsing
> > order in the trees describe the opposition of the two.
> >
> > These relative asymmetries **show** me a little better why you have for a
> > long time wanted to concentrate on developing verbs in only one of the
> two
> > ways (using forks and not conjunctions, in your case) to limit
> complexity.
> >
> >
> > On Sat, Jan 23, 2016 at 11:08 PM, Linda A Alvord <
> lindaalvord at verizon.net>
> > wrote:
> >
> > > Guess how this tree will look before you look.
> > >
> > > h=: 13 :'((((%@%:)@-)@+)@*:)y'
> > > 5!:4 <'h'
> > >
> > > Linda
> > >
> > > -----Original Message-----
> > > From: Programming [mailto:programming-bounces at forums.jsoftware.com] On
> > > Behalf Of Linda A Alvord
> > > Sent: Saturday, January 23, 2016 2:01 AM
> > > To: programming at jsoftware.com
> > > Subject: Re: [Jprogramming] @ and @: (atop and at)
> > >
> > > Henry, Your explanation of how the conjunctions are parsed helped make
> > the
> > > tree diagrams make more sense. I gave up my idea.
> > >
> > >
> > >
> > >    f=: 13 :'(%@(%:@(-@(+@*:))))y'
> > >
> > >    5!:4 <'f'
> > >
> > >       ┌─ %
> > >
> > > ── @ ─┤     ┌─ %:
> > >
> > >       └─ @ ─┤     ┌─ -
> > >
> > >             └─ @ ─┤     ┌─ +
> > >
> > >                   └─ @ ─┴─ *:
> > >
> > >    g=: 13 :'%@%:@- at +@*:y'
> > >
> > >    5!:4 <'g'
> > >
> > >                         ┌─ %
> > >
> > >                   ┌─ @ ─┴─ %:
> > >
> > >             ┌─ @ ─┴─ -
> > >
> > >       ┌─ @ ─┴─ +
> > >
> > > ── @ ─┴─ *:
> > >
> > >
> > > --
> > (B=)
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> >
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-- 
(B=) <-----my sig
Brian Schott