g=: [: [EMAIL PROTECTED] [: /:~@":"0 (>:i.6) * ]
   g 142857
1
   g 142857142857x
1
   g  ". 'x' ,~ , (?1000) $ ,: '142857'
1



----- Original Message -----
From: Roger Hui <[EMAIL PROTECTED]>
Date: Tuesday, March 20, 2007 3:08 am
Subject: Re: [Jprogramming] monad vs. dyad

> Cute.  142857 is immediately recognizable to me as
> the decimal expansion of %7 .
> 
> 1. The dyad =/ is the function table for = .
> The monad =/ inserts = between items of the
> argument.  Thus =/1 4 2 8 5 7 is 1=4=2=8=5=7 which,
> because of the right-to-left evaluation and because
> x=y is 0 or 1, does not mean the same as it does
> in conventional math notation.
> 
> 2. The left-hand-side of assignment must be a name
> or a string satisfying certain conditions.
> 
> 4. The "capped fork" [: f g is the same as f@:g .
> 
> 3. Yes, for example:
>   >: ^: (1 < [: [EMAIL PROTECTED] [: /:~@":"0 (>:i.6) * ]) ^: _ ] 1
> 142857
> 
> f^:proposition^:_ y is a common construct, meaning
> z=. y
> while. proposition y do. z=. f z end.
> 
> 
> 
> ----- Original Message -----
> From: Geoff Canyon <[EMAIL PROTECTED]>
> Date: Tuesday, March 20, 2007 1:15 am
> Subject: Re: [Jprogramming] monad vs. dyad
> 
> > Thanks for the help!
> > 
> > 0 is the obvious answer, but there are other numbers that meet 
> > this  
> > criteria.
> > 
> > I modified your code like this:
> > 
> >    f=:((1<])#@:~.@:(/:~@:":"0)@:((>:i.6)*]))+]
> >    (f^:_) 1
> > 
> > And got my answer. This leaves me with the following questions:
> > 
> > 1. So what _does_ =/ mean?
> > 2. If it doesn't mean anything, is it possible for me (any user) 
> > to  
> > define =/=:1&=#]  ? (apparently not)
> > 3. Is there a way to compose my two lines above into a single 
> command?> 4. To avoid all the @: above, should I be looking for 
> ways to turn 
> > it  
> > into forks and/or hooks?
> > 
> > I have to add: my brain hurts! (in a good way)
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