I am referring to the verbs produced by ( u=. 2 2 $ +/ ; |: ; |. ; -/ . *
), ( w=. tf T ) and ( v=. T(4 :'<y`:0 x'"_ 0&) ).  Although (v) and (w) are
equivalent in the sense that they should produce the same results when
given the same argument they are not the same in the following sense: ( tf
T ) resolves into a verb defined exactly as (u), namely (  2 2 $ +/ ; |: ;
|. ; -/ . * ), whereas ( T(4 :'<y`:0 x'"_ 0&) ) resolves into an equivalent
verb with a different definition, namely
( 4 : '<y`:0 x'"_ 0&(2
2$(<(<,'/'),<,<,'+'),(<'|:'),(<'|.'),<(<,'.'),<(<(<,'/'),<,<,'-'),<,'*') ).

Moreover, since the verbs (u) and (w) are, in the end, defined exactly in
the same manner, their atomic representations are also the same,

   ar=. 5!:1@<

   (ar'u') -: (ar'w')
1
In contrast, the verb (v) has a different atomic representation,

   (ar'u') -: (ar'v')
0
That was the intended significance of,

   (tf T) `'' -: u f.`'' NB. (tf T) is (2 2 $ +/ ; |: ; |. ; -/ . *)
1
in my original post.

I hope this helps.

On Tue, Apr 16, 2013 at 9:48 AM, Raul Miller <[email protected]> wrote:

> Now I'm thinking you want a nice display using the built-in display
> mechanisms for the result (to be distinguished from the code which
> generates that result).  In other words (except you would not do it
> this way), something like:
>
>    (3 :'(($y)$(4 :''(x`:6;y`:6)`''''''''''/,y)`:6)`'''''T)`:6
>
> I could make that prettier, of course, but single line execution is
> nice enough for discussion purposes.
>
> (Here, also, the shape has been factored out of the computation, and
> is applied as a final step. But I am currently thinking that that's a
> means to the end, rather than the end itself.)
>
>
> On Tue, Apr 16, 2013 at 9:00 AM, Jose Mario Quintana
> <[email protected]> wrote:
> > "Would you consider Tfixed`:0 as being U?"
> >
> > No.  Maybe the following can clarify what I tried to convey:
> >
> >    u=. 2 2 $ +/ ; |: ; |. ; -/ . *
> >    v=. T(4 :'<y`:0 x'"_ 0&)
> >    w=. tf T
> >
> >    u
> > 2 2 $ +/ ; |: ; |. ; -/ .*
> >
> >    v
> > 4 : '<y`:0 x'"_ 0&(2
> > 2$(<(<,'/'),<,<,'+'),(<'|:'),(<'|.'),<(<,'.'),<(<(<,'/'),<,<,'-'),<,'*')
> >
> >    w
> > 2 2 $ +/ ; |: ; |. ; -/ .*
> >
> >
> >
> >
> > On Tue, Apr 16, 2013 at 12:14 AM, Raul Miller <[email protected]>
> wrote:
> >
> >> On Mon, Apr 15, 2013 at 8:28 PM, Jose Mario Quintana
> >> <[email protected]> wrote:
> >> > So far no solution is transforming T into U and perhaps emulating U is
> >> what
> >> > was meant, as in
> >> > Raul's solution T(4 :'<y`:0 x'"_ 0&).
> >>
> >> I don't understand what you mean here.
> >>
> >> How was my solution "not U"?
> >>
> >> What is the difference between being U and emulating U?
> >>
> >> I think the distinction you are drawing here has to do with
> >> replicating some functionality in each cell of the table of verbs, but
> >> if that's the case I don't know why it's important. Those approaches
> >> take more code to implement and also result in a table with different
> >> cells.
> >>
> >> Put differently, `:0 was the probably the right approach - the problem
> >> was that the verbs were not conformable. Fixing the "problem" means
> >> changing the verbs or changing the environment in which they operate.
> >> If you're going to change the verbs, I'd change them from the start,
> >> or I'd use something like:
> >>
> >>    T =: 2 2 $ +/`|:`|.`(-/ .*)
> >>    Tfixed=: 3 :'{.''''`(<@(y`:0))'"0 T
> >>
> >>    Tfixed`:0 i. 2 2
> >> +---+---+
> >> |2 4|0 2|
> >> |   |1 3|
> >> +---+---+
> >> |2 3|_2 |
> >> |0 1|   |
> >> +---+---+
> >>
> >> So...
> >>
> >> Would you consider Tfixed`:0 as being U?
> >>
> >> Thanks,
> >>
> >> --
> >> Raul
> >> ----------------------------------------------------------------------
> >> For information about J forums see http://www.jsoftware.com/forums.htm
> >>
> > ----------------------------------------------------------------------
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