I thought about that. While the result of  x u/ y  is the same 
as  x u"(lu,_) y  they are still equivalent to the same extent
as 2*2 is equivalent to 2+2. But how useful is that? 
For J it is especially important to concern not only about 
the results of noun-valued expressions, but construction of 
tacit definitions. And it's the interplay of ranks and operators that
glue the tacit definitions together in the resulting tacit pipeline.

In addition, it creates confusion, and in the
Primer it already says that the VERB (v/), not the 
noun-expression, has the (lu,_) rank:

  The derived verb v/ has a left rank that is the left 
  rank of v and a right rank of _



--- Roger Hui <[EMAIL PROTECTED]> wrote:

> It did not say that u/ is equivalent to u"(lu,_) ,
> just that x u/ y is equivalent to x u"(lu,_) y .
> 
> 
> 
> ----- Original Message -----
> From: Oleg Kobchenko <[EMAIL PROTECTED]>
> Date: Friday, September 22, 2006 1:36 pm
> Subject: Re: Cell (was Re: [Jgeneral] I expect a table of ordered pairs for 
> this)
> 
> > >  Thus x u/ y is equivalent to 
> > >  x  u"(lu,_) y where lu is the left rank of u .
> > 
> >   (i.3) <@(+"0 _) i.3
> > +-----+-----+-----+
> > |0 1 2|1 2 3|2 3 4|
> > +-----+-----+-----+
> >   (i.3) <@(+/) i.3
> > +-----+
> > |0 1 2|
> > |1 2 3|
> > |2 3 4|
> > +-----+
> > 
> > That does not look equivalent.
> > 
> > What it should say: x u/ y is equivalent to x u"(lu,_)"_ y
> > 
> >   (i.3) <@(+"0 _"_) i.3
> > +-----+
> > |0 1 2|
> > |1 2 3|
> > |2 3 4|
> > +-----+
> > 
> > 
> > --- Roger Hui <[EMAIL PROTECTED]> wrote:
> > 
> > > You should also read section II b of the dictionary:
> > > 
> > > http://www.jsoftware.com/help/dictionary/dictb.htm
> > > 
> > > and the immediately following sentence in the 
> > > dictionary entry for / :
> > > 
> > >  In general, each cell of x is applied to the 
> > >  entire of y .  Thus x u/ y is equivalent to 
> > >  x  u"(lu,_) y where lu is the left rank of u .
> 
> 
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
> 


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