I don't see that the dyad I. (interval index) belongs with the others.
I assume you mean |. (rotate).
{
{.
}.
|.
A.
You can not have the new behaviour (boxed left arguments)
for {. }. |. and still be compatible. The left ranks are wrong.
----- Original Message -----
From: Joey K Tuttle <[email protected]>
Date: Wednesday, December 16, 2009 10:57
Subject: Re: [Jprogramming] Proposed extension to A. (incompatible)
To: Programming forum <[email protected]>
> If such an extension was to be implemented I think it would make
> sense
> to have similar arguments work with I. {. {. as well. Current
> behavior
> could be left as a convenience/back compatibility.
>
> Sent from my iPod - excuse terseness and typos.
>
> - joey
>
>
>
> On Dec 16, 2009, at 10:41, Roger Hui <[email protected]> wrote:
>
> > The extension can be more readily accommodated (i.e.,
> > with backward compatibility) if the left argument were boxed.
> > Likewise, if we were designing from scratch (which we are not),
> > we would be tempted to box the left arguments of the dyads
> |. {. }. .
> >
> >
> >
> > ----- Original Message -----
> > From: Dan Bron <[email protected]>
> > Date: Wednesday, December 16, 2009 9:59
> > Subject: [Jprogramming] Proposed extension to A. (incompatible)
> > To: 'Programming forum' <[email protected]>
> >
> >> I would like to propose an extension to dyad
> >> A. Specifically, I would like dyad A. to
> >> interpret left-arguments in a way similar
> >> to |. and {. , where each atom
> >> of x corresponds to an axis of
> >> y . For example, with the new
> >> definition, the phrase (0
> >> _1 A. i. 4 5) would reverse the columns of y, yielding the
> >> same results as (_1 A.&.|: i. 4 5) does with the
> >> current definition.
> >> Similar statements apply to higher dimensions; I can post a
> >> model (using |:) if that's helpful.
> >>
> >> Of course, right now, the ranks of dyad A. are
> >> 0 _ . The new definition of
> >> A. would require them to be 1
> >> _ , so
> >> extension is not backwards compatible. But because of the
> >> way A. is typically used, I doubt it would break
> >> much code in practice.
> >> Furthermore, the fix is trivial; substitute A."_ 0
> >> _ for all uses of A.
> >>
> >> I believe the extension would be useful; more and more I find
> >> myself wanting direct access non-leading axes of an array,
> and I now
> >> make heavy use of (boxes <;.n y), (list {. y),
> >> (list |. y) etc. This extension to
> >> A. would make a nice companion to another
> >> proposal I made:
> >>
> http://www.jsoftware.com/jwiki/System/Interpreter/Requests#redefineu.3B.0y
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