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Re: Matplotlib X-axis timezone trouble

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On Tue, 30 Jun 2015 12:11:31 +1000, Chris Angelico <rosuav@gmail.com> wrote:
> On Tue, Jun 30, 2015 at 10:56 AM, Peter Pearson
><pkpearson@nowhere.invalid> wrote:
>> The following code produces a plot with a line running from (9:30, 0) to
>> (10:30, 1), not from (8:30, 0) to (9:30, 1) as I desire.
>>
>> pacific = pytz.timezone("US/Pacific")
>> plt.plot([datetime.datetime(2014, 10, 7, 8, 30, tzinfo=pacific),
>>           datetime.datetime(2014, 10, 7, 9, 30, tzinfo=pacific)],
>>          [0,1], marker="o", color="green")
>
> Sounds to me like a bug in DST handling - in October 2014, Los Angeles
> was on Pacific Daylight Time, which would give a one-hour offset if
> matplotlib is handling things on the basis of Pacific Standard Time. I
> don't know if that helps at all with figuring out a solution, though.

Thanks, I think you're onto something.  Points in a non-daylight-saving
month get plotted correctly:

plt.plot([datetime.datetime(2014, 12, 7, 8, 30, tzinfo=pacific),
          datetime.datetime(2014, 12, 7, 9, 30, tzinfo=pacific)],
         [0,1], marker="o", color="green")

Time zones teem with sneaky software problems, and so does daylight-saving
time, so this problem might strain my brain.  Maybe it's going to turn
out that my expectations are unreasonable . . . as in, "Well, smarty pants,
how do you want the axis labelled when the abscissas straddle the
beginning of daylight-saving time?"  I'll research and digest.

-- 
To email me, substitute nowhere->runbox, invalid->com.

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Thread

Matplotlib X-axis timezone trouble Peter Pearson <pkpearson@nowhere.invalid> - 2015-06-30 00:56 +0000
  Re: Matplotlib X-axis timezone trouble Laura Creighton <lac@openend.se> - 2015-06-30 04:03 +0200
    Re: Matplotlib X-axis timezone trouble Peter Pearson <pkpearson@nowhere.invalid> - 2015-06-30 04:57 +0000
  Re: Matplotlib X-axis timezone trouble Chris Angelico <rosuav@gmail.com> - 2015-06-30 12:11 +1000
    Re: Matplotlib X-axis timezone trouble Peter Pearson <pkpearson@nowhere.invalid> - 2015-06-30 04:49 +0000
      Re: Matplotlib X-axis timezone trouble Chris Angelico <rosuav@gmail.com> - 2015-06-30 17:01 +1000
        Re: Matplotlib X-axis timezone trouble Peter Pearson <pkpearson@nowhere.invalid> - 2015-06-30 16:42 +0000
          Re: Matplotlib X-axis timezone trouble Chris Angelico <rosuav@gmail.com> - 2015-07-01 02:55 +1000
  Re: Matplotlib X-axis timezone trouble Peter Pearson <pkpearson@nowhere.invalid> - 2015-07-01 05:50 +0000
    Re: Matplotlib X-axis timezone trouble Chris Angelico <rosuav@gmail.com> - 2015-07-01 17:15 +1000
      Datetime timezone trouble (was: Matplotlib X-axis timezone trouble) Peter Pearson <pkpearson@nowhere.invalid> - 2015-07-01 16:36 +0000
        Re: Datetime timezone trouble (was: Matplotlib X-axis timezone trouble) Ian Kelly <ian.g.kelly@gmail.com> - 2015-07-01 10:55 -0600
          Re: Datetime timezone trouble (was: Matplotlib X-axis timezone trouble) Peter Pearson <pkpearson@nowhere.invalid> - 2015-07-01 19:09 +0000
        Re: Datetime timezone trouble (was: Matplotlib X-axis timezone trouble) Chris Angelico <rosuav@gmail.com> - 2015-07-02 03:08 +1000
  Re: Matplotlib X-axis timezone trouble Akira Li <4kir4.1i@gmail.com> - 2015-07-04 07:29 +0300
    Re: Matplotlib X-axis timezone trouble [SOLVED] Peter Pearson <pkpearson@nowhere.invalid> - 2015-07-04 17:37 +0000
  Re: Matplotlib X-axis timezone trouble Tony the Tiger <tony@tiger.invalid> - 2015-07-09 19:50 +0000
    Re: Matplotlib X-axis timezone trouble Peter Pearson <pkpearson@nowhere.invalid> - 2015-07-10 16:15 +0000

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