Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!news-2.dfn.de!news.dfn.de!storethat.news.telefonica.de!feedme.news.telefonica.de!telefonica.de!diesel.cu.mi.it!.POSTED!not-for-mail
From: giacomo boffi <pecore@pascolo.net>
Newsgroups: comp.lang.python
Subject: Re: Handling 3 operands in an expression without raising an exception
Date: Sun, 29 Sep 2013 23:39:03 +0200
Organization: The Sun and the Rain.
Lines: 25
Message-ID: <87a9ivi9zc.fsf@pascolo.net>
References: <l20njn$uhh$1@dont-email.me> <pan.2013.09.26.08.55.29.461000@nowhere.com> <l210c2$95b$1@dont-email.me> <mailman.345.1380190345.18130.python-list@python.org> <l211m1$f3b$1@dont-email.me> <mailman.348.1380192089.18130.python-list@python.org> <l213jr$p9j$1@dont-email.me> <mailman.350.1380194717.18130.python-list@python.org> <l219tq$o2c$1@dont-email.me> <mailman.354.1380200021.18130.python-list@python.org> <l21d5u$cit$1@dont-email.me> <mailman.355.1380205373.18130.python-list@python.org> <l21p2r$ilf$1@dont-email.me> <l224n6$oak$1@dont-email.me> <l22bkl$9ds$1@dont-email.me> <mailman.372.1380236161.18130.python-list@python.org> <l23ijp$jka$1@dont-email.me> <87eh87ir51.fsf@pascolo.net> <mailman.453.1380470867.18130.python-list@python.org>
NNTP-Posting-Host: ppp-144-7.21-151.libero.it
Mime-Version: 1.0
Content-Type: text/plain; charset=iso-8859-7
Content-Transfer-Encoding: 8bit
X-Trace: virtdiesel.mng.cu.mi.it 1380490743 25223 151.21.7.144 (29 Sep 2013 21:39:03 GMT)
X-Complaints-To: abuse@diesel.cu.mi.it
NNTP-Posting-Date: Sun, 29 Sep 2013 21:39:03 +0000 (UTC)
User-Agent: Gnus/5.1008 (Gnus v5.10.8) XEmacs/21.5-b32 (linux)
Cancel-Lock: sha1:wg6COpoF9pHnbgOXSffpvFpfyB4=
Xref: csiph.com comp.lang.python:55038

Joel Goldstick <joel.goldstick@gmail.com> writes:

> On Sun, Sep 29, 2013 at 11:28 AM, giacomo boffi <pecore@pascolo.net> wrote:
>
>     Νίκος <nikos.gr33k@gmail.com> writes:
>
>     > IF it can also be written in one-line
>
>     def f(x,n,w):return(lambda y=f(x[::2],n/2,w[::2]),z=f(x[1::2],n/2,w
>     [::2]):reduce(lambda x,y:x+y,zip(*[(y[k]+w[k]*z[k],y[k]-w[k]*z[k]) for k in
>     range(n/2)])))()if n>1 else x
>
> I've been reading along and learning some really obscure coding
> patterns.

well, the obscure patterns aren't mine, they were contributed by some
it.comp.python regulars, to which credit is due if credit is due
(please ask google groups for the individual contributions)

> why?

to show a recreational one liner from which Νίκος could learn
something, one way or another
-- 
X  = f(x,n,[exp(-2*pi*1j*k/n) for k in range(n/2)])