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Re: Matplotlib X-axis timezone trouble

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On Tue, 30 Jun 2015 04:03:57 +0200, Laura Creighton <lac@openend.se> wrote:
> In a message of 30 Jun 2015 00:56:26 +0000, Peter Pearson writes:
>>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.
>>
>>If I use timezone None instead of pacific, the plot is as desired, but
>>of course that doesn't solve the general problem of which this is a
>>much-reduced example.
>>
>>If I use timezone US/Central, I get the same (bad) plot.
>>
>>import matplotlib.pyplot as plt
>>import datetime
>>import pytz
>>pacific = pytz.timezone("US/Pacific")
>>fig = plt.figure()
>>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")
>>fig.autofmt_xdate()
>>plt.show()
>>
>>Does anybody know why this shift is occurring?  Is Matplotlib
>>confused about what timezone to use in labeling the axis?  How
>>would I tell it what timezone to use (preferably explicitly in
>>the code, not in matplotlibrc)?
[snip]
>
> I know that your problem is that all your times are in UTC, even
> though you do not want this.  I had this too.  I forget what I did.

Actually, UTC is very helpful in this project, which has to
deal with timestamped data from various timezones.  After I finally
stumbled upon datetime's astimezone() method, things seemed to be
going smoothly . . .

> I do not know if this solution from stackoverflow.com will work for
> you -- it is definitely different from what I did, but that does
> not in any way make it wrong.  Try and see?  and report back?
>
> http://stackoverflow.com/questions/4485607/matplotlib-plot-date-keeping-times-in-utc-even-with-custom-timezone

Thanks for the pointer.  I'll report back.


-- 
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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