I guess it takes a long time for anyone to realize the power of rank.

https://groups.google.com/forum/?hl=is#!searchin/j-programming/rank/j-programming/XwvPm9UhCt8/lMyXcnT_6wIJ

Some people claim that if you do not understand rank you do not
understand J

2011/11/4 Roger Hui <[email protected]>

> When "table" x f/y was introduced (at the very beginning) we did not
> fully comprehend the power of the rank operator.  If I had realized
> that table was just x f"(lr,_) y, where lr is the left rank of f, I
> might have tried to argue strongly for using the dyad f/ for something
> else.
>
>
>
> On Fri, Nov 4, 2011 at 2:15 AM, Henry Rich <[email protected]> wrote:
> > Just a quibble with terminology: 'item' means _1-cell.  That concept
> > does not apply here.  If you define 'l-cell' to be the left rank of the
> > verb, and 'r-cell' the right rank, you could say
> >
> > ...it loops through all the l-cells of x, then for each of those, all
> > the r-cells of y...
> >
> > Henry Rich
> >
> > On 11/4/2011 12:13 AM, Marshall Lochbaum wrote:
> >> * has rank 0 already, so it isn't necessary. The definition of / is
> that it
> >> applies the verb with rank (left rank),_ . Essentially, this means that
> it
> >> loops through all the items of x, then for each of those, all the items
> of
> >> y, where an "item" is an item with the left rank of the verb. If you try
> >> magic/~ a with magic having rank _ (because it's a fork), you just get
> (a
> >> magic"_ _"_ _ a), which simply applies magic regularly.
> >>
> >> Marshall
> >>
> >> On Thu, Nov 3, 2011 at 11:57 PM, Ricardo Forno<[email protected]
> >wrote:
> >>
> >>> I have this verb:
> >>> magic =: * %>:@(+:@*) - +
> >>> that I use only as a dyad, and, say,
> >>> a =: 0.1 * i. 10
> >>> If I want to get a table of the * verb, I  write:
> >>> a * / a
> >>> If I write
> >>> a magic / a
> >>> I dont get a table. To get a table, I have to write:
> >>> a magic"0 / a
> >>> Why is it so, since both * and magic may be used as dyads?
> >>> Thanks.
> >>>
> >>>
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-- 
Björn Helgason, Verkfræðingur
Fornustekkum II
781 Hornafirði,
t-póst: [email protected]
gsm: +3546985532
twitter: @flugfiskur
http://groups.google.com/group/J-Programming


Tæknikunnátta höndlar hið flókna, sköpunargáfa er meistari einfaldleikans

góður kennari getur stigið á tær án þess að glansinn fari af skónum
          /|_      .-----------------------------------.
         ,'  .\  /  | Með léttri lund verður        |
     ,--'    _,'   | Dagurinn í dag                     |
    /       /       | Enn betri en gærdagurinn  |
   (   -.  |        `-----------------------------------'
   |     ) |         (\_ _/)
  (`-.  '--.)       (='.'=)   ♖♘♗♕♔♙
   `. )----'        (")_(") ☃☠
----------------------------------------------------------------------
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