I think Graham is referring to what would happen 
if the ideas in section 2 of the following article
were implemented.

http://www.jsoftware.com/papers/rank.htm



----- Original Message -----
From: Henry Rich <[EMAIL PROTECTED]>
Date: Tuesday, January 9, 2007 12:02 pm
Subject: RE: [Jprogramming] Re: Why won't this plot?

> I can't quite make J sense of your question, but I suspect
> the root of the problem is the meaning of [EMAIL PROTECTED] .
> 
> [EMAIL PROTECTED] is a new verb, with its own rank (which is taken
> from the rank of v).  So when you write
> 
> [EMAIL PROTECTED] y
> 
> The entire verb [EMAIL PROTECTED] is applied to each atom of y.  For each
> atom, the interpreter executes +. then {.  There is never
> any possibility if executing +. (or {.) over the entire y,
> because {. never sees the entire y.
> 
> The interpreter could choose to recognize [EMAIL PROTECTED] as a special
> combination, in effect making a new primitive out of that
> combination, and then using Integrated Rank Support for
> the combination.  But it doesn't.
> 
> [EMAIL PROTECTED] is a new verb.  Important, but often misunderstood.
> 
> Henry Rich
> 
> 
> 
> > -----Original Message-----
> > From: [EMAIL PROTECTED] 
> > [EMAIL PROTECTED] On Behalf Of 
> > Graham Parkhouse
> > Sent: Tuesday, January 09, 2007 3:51 AM
> > To: [email protected]
> > Subject: [Jprogramming] Re: Why won't this plot?
> > 
> > Henry wrote:
> > 
> > >Your analysis is almost right.  Actually, {."1 benefits
> > >from Integrated Rank Support, which means that the
> > >loop over the operand is a tight inner loop rather than 
> > starting the whole
> > verb up anew for each 1-cell.
> > >
> > >So, [EMAIL PROTECTED] starts {. and +. for each 0-cell, while
> > >{."1@:+. starts +. once and {. once.
> > 
> > Thanks, that's really helpful. I like the concept of integrated rank
> > support. Using an argument of i.30 40 50 there is a noticably 
> shorter> response time if it is prefixed by the second verb. Why 
> > shouldn't integrated
> > rank support be extended to the first verb? I guess it's just 
> > a matter of
> > interpreter sophistication, and no doubt there are pros and 
> > cons to every
> > piece of added complexity.


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