Path: csiph.com!news.mixmin.net!news.unit0.net!news.netfront.net!not-for-mail From: =?UTF-8?Q?Honza_Kr=C3=A1l?= Newsgroups: cz.comp.lang.python Subject: Re: [python] =?utf-8?q?Spojovani_retezcu=3A_=28bylo=3A_Rekurzivn?= =?utf-8?b?w60gZ2VuZXLDoXRvciB2IFB5dGhvbnUgMz8p?= Date: Sun, 28 Aug 2016 17:51:44 +0200 Organization: Netfront http://www.netfront.net/ Lines: 104 Message-ID: References: NNTP-Posting-Host: 94.23.32.179 Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Trace: adenine.netfront.net 1472700350 60661 94.23.32.179 (1 Sep 2016 03:25:50 GMT) X-Complaints-To: news@netfront.net NNTP-Posting-Date: Thu, 1 Sep 2016 03:25:50 +0000 (UTC) To: Konference PyCZ Received-SPF: pass (Address passes the Sender Policy Framework) SPF=MAILFROM; sender=honza.kral@gmail.com; remoteip=::ffff:74.125.82.53; remotehost=; helo=mail-wm0-f53.google.com; receiver=hugo.zagamma.cz; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-transfer-encoding; bh=DCKxCo6rBlk74ep9Y0ebfPkKGOn5KOAiuU9+hbWjJx0=; b=jxmcQ66FugMg/9W4ha1eoGjX/VXtIL5ht8ly0JcRUnf4bntJRF3/ZRYZxGEHdL+Ys1 BYOXBpqjCiHuL3j0HRT/E/gWvQTkcpAxgoefMWNGrg55Dnjp0eqU1mIQxmetcCQHnI0K l+Bh/fgK0/V60/g5wmuMmND6r5ZlP7p8FkqlAu/GlMLHXOdqdTYchj00DOhA0W3pLhWy MGJCd0VeA0TZMLYZorb3TQwlrnrtKfWmCRF27fFWVtR+QujNnNS/wAsCAinsms/slKXr ymw7HNYTZNuFQJPSOJSbUIFXDb2h5DA9/7kTTTCB6q6Pa6C021K7ib9wzcoGmZHfQS6j V6Ig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:content-transfer-encoding; bh=DCKxCo6rBlk74ep9Y0ebfPkKGOn5KOAiuU9+hbWjJx0=; b=K4VCu60aLML1PrMPmX/cLWV+MH5ykBp6lAubT7188A/WYCvlBgMhqDY735IkKEZnJF n3jkzGhMLKywOpDvQqmaRNX1yygNE04xyOH190Q6muga4GZ9cFLsWlqE+4RD+47+ScGA wKjjzhe24KOIGxnl5/SvKAYOOTuxP7jeSQUx1XO3GBopL1C71S91bZCni8IKRi02uLEN SSemsUlsj21FQaP6eyZZaFzU/cFn7AGnzyH7hjWZ6IzrJjey7Y8hfpGwF9lJbsWG7cxs b2l+mOhqNci7nmmIzRgdiwR94PF6kFGciAb4zCjkvv0v7Q+6Yp9SYipD/gknVvuZ2ekz rbgQ== X-Gm-Message-State: AE9vXwMJ6wHejXog7n6ZlNnbH1tfLxij3sYgLEAzrAHW4GRYDh/c3onoaAsSb7zcfNoNvFLxcQmEldCeWdcGXA== X-Received: by 10.28.101.5 with SMTP id z5mr6492093wmb.9.1472399524599; Sun, 28 Aug 2016 08:52:04 -0700 (PDT) In-Reply-To: X-BeenThere: python@py.cz X-Mailman-Version: 2.1.20 Precedence: list List-Id: Konference PyCZ List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com cz.comp.lang.python:3132 Honza Kr=C3=A1l E-Mail: honza.kral@gmail.com Phone: +420 606 678585 2016-08-28 17:40 GMT+02:00 Petr Messner : > D=C3=ADky Honzo za odkaz. > > Jinak - Python, Ruby, Java, C++, na jazyku nez=C3=A1le=C5=BE=C3=AD... Mus= =C3=ADm v=C4=9Bd=C4=9Bt, jestli dan=C3=A1 operace manipuluje s n=C4=9Bkter= =C3=BDm sv=C3=BDm operandem, nebo vytv=C3=A1=C5=99=C3=AD novou hodnotu. A p= roto=C5=BEe jsou stringy v Pythonu immutable, tak jako program=C3=A1tor byc= h m=C4=9Bl tu=C5=A1it, =C5=BEe se bude kop=C3=ADrovat. A d=C3=A1t si pozor = na p=C5=99=C3=ADpady, kdy se bude kop=C3=ADrovat furt dokola. > > =C5=BDe to pypy n=C4=9Bjak um=C3=AD optimalizovat je hezk=C3=A9, ale i kd= ybych ho pou=C5=BE=C3=ADval, tak fakt nen=C3=AD dobr=C3=A9 spol=C3=A9hat se= na to, =C5=BEe mi p=C5=99eklada=C4=8D oprav=C3=AD chybu v samotn=C3=A9m n= =C3=A1vrhu algoritmu. stale plati, ze mnohem dulezitejsi nez kompilator je programator - pouzivam tak to, co dava z hlediska kodu (nikoli kompilatoru nejvetsi smysl). Python s tim pocita a je na to zarizeny. Snazit se o takove optimalizace vetsinou prinasi vice problemu nez uzitku. A to i kdyz odhledneme od problemu spojenych s tim, ze python ma nekolik implementaci ktere se chovaji jinak. > > Petr Messner > > 28. 8. 2016 v 17:04, Honza Kr=C3=A1l : > >> 2016-08-28 16:51 GMT+02:00 Jirka Vejrazka : >>> Jenom poznamka ne okraj: >>> >>> "ned=C4=9Blej skl=C3=A1d=C3=A1n=C3=AD =C5=99et=C4=9Bzc=C5=AF stylem txt= +=3D part, je to stra=C5=A1n=C4=9B pomal=C3=A9 (O(n^2) >>> m=C3=ADsto O(n)).. Z txt si ud=C4=9Blej list a pou=C5=BE=C3=ADvej appen= d: txt.append(part) a na >>> konci "".join(txt)." >>> >>> Tohle platilo nekdy do vydani Pythonu 2.5. V te verzi bylo spojovani re= tezcu >>> pomoci +=3D vyrazne zrychleno a dnes uz to neni takove vykonove omezeni= , jako >>> driv. >> >> Pokud je tech textu vice, .join() je stale lepsi, vice detailu: >> https://youtu.be/odjpaKL-Fsg?t=3D20m45s >> >>> >>> Ale je fakt, ze ''.join pouzivam ze zvyku taky :) >>> >>> Jirka >>> >>>> On 28 August 2016 at 13:52, Petr Messner wrot= e: >>>> >>>> >>>> co takhle tohle? >>>> >>>> >>>> a b c de f g h<= /verse> >>>> >>>> >>>> Oprava: >>>> >>>> a b c de f g >>>> h >>>> >>>> PM >>>> >>>> _______________________________________________ >>>> Python mailing list >>>> python@py.cz >>>> http://www.py.cz/mailman/listinfo/python >>>> >>>> Visit: http://www.py.cz >>> >>> >>> >>> _______________________________________________ >>> Python mailing list >>> python@py.cz >>> http://www.py.cz/mailman/listinfo/python >>> >>> Visit: http://www.py.cz >> _______________________________________________ >> Python mailing list >> python@py.cz >> http://www.py.cz/mailman/listinfo/python >> >> Visit: http://www.py.cz > _______________________________________________ > Python mailing list > python@py.cz > http://www.py.cz/mailman/listinfo/python > > Visit: http://www.py.cz --- news://freenews.netfront.net/ - complaints: news@netfront.net ---