I was enjoying Chris Burke's 1996 essay on "Elegant Programming" -
http://www.jsoftware.com/papers/elegant.htm - but when I tried some of his
examples, one did not work.  The elegant derivation for harmonic mean from
arithmetic mean:

   am=. +/ % #
   hm=. am &. %

When "hm" is used on the argument "2 3 5" as shown in the essay, it returns
the input instead of the answer "2.9032258".  A little investigation
uncovered that the definition of harmonic mean in contemporary J should be

   hm=. am &. (%"_)

It would be nice to have these good examples that work with current J though
it would lose some historical perspective.  Would it be possible to update
this essay to include the currently working code, perhaps with a footnote
indicating the historical evolution of the language?

Regards,

Devon

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