[Jprogramming] A q for starters - composing without forking (% +/ %)

[Devon McCormick]

Caps also appear if you generate a tacit expression using "13 :" e.g.

   13 : '%+/%y'
[: % [: +/ %
   (13 : '%+/%y') 10 20 40
5.7142857
   ([: % [: +/ %) 10 20 40
5.7142857

I like the dual version for this because it's conceptually closer to what is
probably intended by "the inverse of the sum of the inverses" i.e. when
calculating the harmonic mean.

On Thu, Feb 4, 2010 at 5:56 PM, Alex Gian <alexgian at blueyonder.co.uk> wrote:

>
> ...  Cap ( [: ) looks cool too, but I haven't encountered a
> similar construct before.  E.g.  I can't intuitively see why Ric's
> suggestion ( [: % [: +/ % ) isn't ( [: % [: +/ [: % ), guess I'll just
> have to rtfm.
> ...
>  ----------------------------------------------------------------------
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>



-- 
Devon McCormick, CFA
^me^ at acm.
org is my
preferred e-mail