{/ is useful in working with permutations and
permutation groups. For example,
sg=: [: {/\ *./@:(#&>)@:C. $ ,:
produces the subgroup generated by a permutation.
See also:
http://www.jsoftware.com/jwiki/Essays/Symmetric_Array
http://www.jsoftware.com/jwiki/Essays/Permutations
----- Original Message -----
From: Raul Miller <[EMAIL PROTECTED]>
Date: Tuesday, March 20, 2007 8:32 am
Subject: Re: [Jprogramming] monad vs. dyad
> On 3/20/07, Mark D. Niemiec <[EMAIL PROTECTED]> wrote:
> > Since i. and i: return indices and { uses them,
> > {/ and i./ and i:/ could be useful on permutations.
>
> I don't know about i. or i: but
> {/\6#,:?~3
> is mildly amusing.
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