Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!newsfeed.freenet.ag!news2.euro.net!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail
Return-Path: <python-python-list@m.gmane.org>
X-Original-To: python-list@python.org
Delivered-To: python-list@mail.python.org
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=python.org; s=200901; t=1373978810; bh=W4hoj5XmWFZHxvtVygfFurHwiLuGsxnfcTNdButHjWE=; h=To:From:Subject:Date:Message-ID:References:Mime-Version: Content-Type:Content-Transfer-Encoding:In-Reply-To; b=VbhYdjOlCy8yrJH2m5ko6tdJ1q9aX/UzguhvTSxYBye4cTtZY7EpzI+YurzyGpvDg hXOsOAATivscp/P+DKAutpX6N0xECHDlzEIJIVFiVnHTWlOBgwAgKdhXtXgA1c/Irw 0MFVRFh52VIxCaLNJCccXmKg/UdMzzziDHd0AMjU=
X-Spam-Status: OK 0.003
X-Spam-Evidence: '*H*': 0.99; '*S*': 0.00; 'one?': 0.05; 'correct.': 0.07; 'float': 0.07; 'defines': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'from:name:christian heimes': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'subject:values': 0.16; 'from:addr:python.org': 0.16; 'header :User-Agent:1': 0.23; 'header:X-Complaints-To:1': 0.27; 'header :In-Reply-To:1': 0.27; 'chris': 0.29; 'that.': 0.31; 'too.': 0.31; '>>>>': 0.31; 'piece': 0.31; 'question:': 0.31; 'this.': 0.32; "can't": 0.35; 'info': 0.35; 'minimum': 0.38; 'to:addr:python- list': 0.38; 'to:addr:python.org': 0.39; 'received:org': 0.40; 'such': 0.63; 'maximum': 0.63; 'technically': 0.84; 'why?': 0.91
X-Injected-Via-Gmane: http://gmane.org/
To: python-list@python.org
From: Christian Heimes <christian@python.org>
Subject: Re: Floating point minimum and maximum exponent values
Date: Tue, 16 Jul 2013 14:46:36 +0200
References: <ks3bl6$g8o$1@speranza.aioe.org> <CAPTjJmqzAvXr2t71M5SnEXp8-Axsy-SPQrGiHU7nD-c2FqVqXw@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
X-Gmane-NNTP-Posting-Host: smtp.semantics.de
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130510 Thunderbird/17.0.6
In-Reply-To: <CAPTjJmqzAvXr2t71M5SnEXp8-Axsy-SPQrGiHU7nD-c2FqVqXw@mail.gmail.com>
X-Enigmail-Version: 1.4.6
X-BeenThere: python-list@python.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: General discussion list for the Python programming language <python-list.python.org>
List-Unsubscribe: <http://mail.python.org/mailman/options/python-list>, <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive: <http://mail.python.org/pipermail/python-list/>
List-Post: <mailto:python-list@python.org>
List-Help: <mailto:python-list-request@python.org?subject=help>
List-Subscribe: <http://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
Newsgroups: comp.lang.python
Message-ID: <mailman.4770.1373978811.3114.python-list@python.org>
Lines: 19
NNTP-Posting-Host: 2001:888:2000:d::a6
X-Trace: 1373978811 news.xs4all.nl 15926 [2001:888:2000:d::a6]:47843
X-Complaints-To: abuse@xs4all.nl
Xref: csiph.com comp.lang.python:50742

Am 16.07.2013 14:04, schrieb Chris Angelico:
> Piece of extreme oddity, this.
> 
>>>> help(sys.float_info)
> .... lots of other info ...
>  |  max_exp
>  |      DBL_MAX_EXP -- maximum int e such that radix**(e-1) is representable
>  |
>  |  min_exp
>  |      DBL_MIN_EXP -- minimum int e such that radix**(e-1) is a
> normalized float
> ....
> 
> So it's technically correct. Followup question: Why is it off by one?

Because float.h defines DBL_MAX_EXP like that.

Why? I can't tell, too.