Path: csiph.com!usenet.pasdenom.info!weretis.net!feeder4.news.weretis.net!feeds.phibee-telecom.net!newsfeed.xs4all.nl!newsfeed7.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.043 X-Spam-Evidence: '*H*': 0.91; '*S*': 0.00; 'url:sourceforge': 0.03; 'dst': 0.07; 'boundaries.': 0.09; 'python': 0.11; 'appropriate': 0.14; 'wed,': 0.15; '2.7.3': 0.16; 'instead:': 0.16; 'offsets': 0.16; 'utc.': 0.16; 'wrote:': 0.16; '>>>': 0.20; 'am,': 0.23; '2015': 0.23; 'tried': 0.24; 'import': 0.24; 'header:In-Reply- To:1': 0.24; 'second': 0.24; 'chris': 0.26; 'message- id:@mail.gmail.com': 0.28; "we're": 0.30; 'maybe': 0.31; 'supposed': 0.31; "can't": 0.32; 'skip:p 30': 0.32; 'pacific': 0.33; 'case,': 0.34; 'received:google.com': 0.34; 'wrong': 0.35; 'to:addr:python-list': 0.35; 'something': 0.35; 'but': 0.36; 'should': 0.37; 'subject:: ': 0.37; '12,': 0.37; 'version': 0.38; 'skip:p 20': 0.38; 'to:addr:python.org': 0.39; 'easily': 0.39; 'subject:-': 0.39; 'skip:t 20': 0.40; 'subject: (': 0.40; 'your': 0.60; 'simple': 0.61; 'show': 0.62; 'mar': 0.65; 'hour': 0.69; 'jul': 0.72; 'saw': 0.76; '+1000,': 0.84; 'converter,': 0.84; 'to:name:python': 0.84; '2014,': 0.91 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-type; bh=go/a9/zp0Qc0BCb6R4ZGBRnSG/Ud16vdl7/ZWfqfBSI=; b=c3h2WA8fmJz/iOp+0HJQkC8RU/0inTyKlskoojJiPnYnhOZ8yhAANgLHxiB2ywUo7V dHWGefRLcaZz5su7QMzRDgkx6vnq6AqlgBkFBxpqj+C9TAuIXYnXTwCNd0rT85hixeZ0 Nuwc4yjyRPBkxMyjxx8y3DWBHX4i4pzkzI7MGXw9zwieC/N0TPj2eTX9JXUnTG2rg7xU QLDlxl3BWjvf022WjM89tk9zU4I++e9FVG6yGv7M9TwLE6Qh5gAIJ/HVxr3MtFazPYfA 5UKB9Kc4lRe8NRzFazHdQMf0Qo1+dccuWJud/IU2lPEmWt2PX0JVz68Vild++pU1WtxL AE/Q== X-Received: by 10.129.94.7 with SMTP id s7mr34083366ywb.111.1435769742261; Wed, 01 Jul 2015 09:55:42 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: From: Ian Kelly Date: Wed, 1 Jul 2015 10:55:02 -0600 Subject: Re: Datetime timezone trouble (was: Matplotlib X-axis timezone trouble) To: Python Content-Type: text/plain; charset=UTF-8 X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.20+ Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 35 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1435769750 news.xs4all.nl 2837 [2001:888:2000:d::a6]:38901 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:93380 On Wed, Jul 1, 2015 at 10:36 AM, Peter Pearson wrote: > On Wed, 1 Jul 2015 17:15:38 +1000, Chris Angelico wrote: >> >> Interestingly, when I tried this (pytz version 2015.4, Python 2.7.9, >> Debian Jessie), I saw utcoffset() showing (-1, 58020) for both. That >> seems... odd. And I can't fault your dates - those definitely ought to >> be easily inside and easily outside the DST boundaries. When I try >> those dates in an unrelated time converter, they do show seven- and >> eight- hour offsets to UTC. Maybe we're both misunderstanding the >> meaning of utcoffset()? > > Here's a very simple demonstration that either something is wrong > or I don't understand how datetime and tzinfo are supposed to work: > > $ python > Python 2.7.3 (default, Mar 13 2014, 11:03:55) >>>> from pytz import timezone >>>> from datetime import datetime >>>> pacific = timezone("US/Pacific") >>>> print(datetime(2014, 7, 7, 12, tzinfo=pacific)) > 2014-07-07 12:00:00-08:00 >>>> print(datetime(2014, 1, 7, 12, tzinfo=pacific)) > 2014-01-07 12:00:00-08:00 >>>> > > The "-08:00" is appropriate in the second (January) case, but the > first case is in July, and should have "-07:00". Use this instead: >>> print(pacific.localize(datetime(2014, 7, 7, 12))) 2014-07-07 12:00:00-07:00 See http://pytz.sourceforge.net/#localized-times-and-date-arithmetic