Re: [matplotlib-devel] errorbar - end bars not visible

[Damon M. <dam...@gm...>]

On Sun, Jan 27, 2013 at 12:28 PM, Neal Becker <ndb...@gm...> wrote:
> Damon McDougall wrote:
>
>> On Sun, Jan 27, 2013 at 11:51 AM, Neal Becker
>> <ndb...@gm...> wrote:
>>> Damon McDougall wrote:
>>>
>>>> On Sun, Jan 27, 2013 at 8:56 AM, Neal Becker
>>>> <ndb...@gm...> wrote:
>>>>> Simple example: the bars on the two x axis ends are not visible.
>>>>>
>>>>> x = [3, 6, 10]
>>>>> y = [1, 2, 3]
>>>>> import matplotlib.pyplot as plt
>>>>>
>>>>> plt.errorbar (x, y, 0.2)
>>>>
>>>> Try adding a plt.xlim(2, 11) here.
>>>>
>>>>> plt.show()
>>>>>
>>> Yes that'll fix it - but ideally autoscaling should work correctly.
>>
>> That behaviour of autoscale appears to be consistent with
>> plt.plot(range(3)), for example.  That is, the axis limits butt up
>> against the plotted data.
>>
>> By 'work correctly', do you mean that the axis limits should be padded
>> so there is a whitespace border surrounding the data being plotted?
>>
>
> I think you'll agree the original result in not visually appealing or clear.
> The most obvious way to improve it would be to select axis limits a bit larger.
> At least large enough to completely show the error bar; I suspect a bit of
> whitespace would be even more clear.

Indeed, I do agree.

I have actually changed my mind about this behaviour being consistent
with plt.plot. I feel like the 'feet' on the error bars should be
taken into account during the autoscaling procedure. This will result
in the autoscaling procedure adding a small amount of whitespace such
that the feet are then visible after a call to plt.show().

I have opened a new issue on our github issue tracker. See
https://github.com/matplotlib/matplotlib/issues/1711

Thanks for reporting the problem, Neal.

-- 
Damon McDougall
http://www.damon-is-a-geek.com
Institute for Computational Engineering Sciences
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