The idea can be put many ways.  Here's one:

x&u y

should be more common or useful than

x u&y


So, in x | y, x is the modulus because you are more likely to
take the remainder of a bunch of numbers with the same modulus
rather than remainders of the same number with different moduli.

The rule comes about because x u^:_1 y is defined as (x&u)^:_1 .

% e. -. (and arguably -)  are defined incorrectly according to this rule, and
in each case the reason is conformance to pre-J mathematical
notation.

Henry Rich


> -----Original Message-----
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED] On Behalf Of R.A. MacDonald
> Sent: Wednesday, May 23, 2007 2:34 PM
> To: General forum
> Subject: Re: [Jgeneral] Why does the Residue function take 
> its arguments in"reverse" order
> 
> Hello Terrence;
> 
> Given that this ordering is as old as APL, thus as old as I 
> am, and I do 
> not recall having seen an explanation, I would also be 
> interested in one.
> 
> A thought: the #: (Antibase) verb follows the same pattern, 
> as did APL's 
> decode (or was it encode? dualities always throw me) with a 
> default left 
> argument of 2 in the monadic case. It sctually returns the 
> same result 
> when the left argument is a scalar:
> 
>     3 #: 10
> 1
>      3 | 10  NB. Veery intestingk.
> 1
> 
> Nitpicky questions are the new poster's job. If you want negative 
> reactions to a novice, ask a Perl "monk" a question.
> 
> Terrence Brannon wrote:
> > It seems that the Residue function should follow the same 
> argument order as %
> >
> > It does not seem consistent or intuitive for the arguments 
> to be reversed.
> >
> > What motivated this decision? I spent 5 minutes about to 
> tear my hair out trying
> > to figure out the results I was getting from Residue.
> >
> >  7 % 2
> > 3.5
> >    2 | 7    NB. would be 7 | 2 if I were designing J :)
> > 1
> >
> >
> > I'm sorry to ask what seem like such nitpicky little 
> questions, but I got a
> > great answer regarding Passive, so perhaps I am just 
> ignorant of some loftier
> > motivation for such argument calling conventions.
> >
> >
> > 
> ----------------------------------------------------------------------
> > For information about J forums see 
> http://www.jsoftware.com/forums.htm
> >
> >   
> 
> -- 
> later ...
> <pre>---------------------------------------------------------
> ---------------
> |\/| Randy A MacDonald   | APL: If you can say it, it's done.. (ram)
> |/\| [EMAIL PROTECTED]  |
> |\ |                     | The only real problem with APL is that
> BSc(Math) UNBF'83        | it is "still ahead of its time."
> Sapere Aude              |     - Morten Kromberg
> Natural Born APL'er      | Looking for a whip-smart APL 
> developer <a href="mailto:[EMAIL PROTECTED]">Send me a note</a>
> -----------------------------------------------------(INTP)---
> -{ gnat }-</pre>
> 
> ----------------------------------------------------------------------
> For information about J forums see 
> http://www.jsoftware.com/forums.htm

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