On 9/14/07, neville holmes <[EMAIL PROTECTED]> wrote:
> {.[.}.
> so that the adverb
> a =. {.[.}.
> would allow f a x to apply f between the head of x and the
> behead of x. Similarly, x f a y would use x {. y and x }. y as
> arguments for f.
a=: /(@({. ,: }.))
+ a 2 3 5 7
5 7 9
2 + a 10^i.4
101 1010
> Other examples:
>
> b =. ] ,: [. NB. adverb
>
> then f b x would stack x over f x and x f b y would stack y
> over x f y.
b=: ^:0 1
+/ b i.3
0 1 2
3 0 0
3 *b 4
4 12
> There are ways of defining such adverbs and conjunctions
> without [. and ]. I suppose, but surely [. and ]. would make
> such constructs much easier to produce and understand.
J's [. and ]. (before they were omitted) did not seem to produce
easy to understand expressions. (The style used in my 'a',
above, is somewhat representative of how you would use those
symbols -- though a is somewhat simpler than those kinds of
examples.)
--
Raul
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