Improve layout of plots with DateTimeIndex

Tell us about it

Plots with dates on their x axis can be typeset poorly. Here is an example from https://docs.pymc.io/notebooks/getting_started.html

The x coordinate here is a DateTimeIndex:

{'date': DatetimeIndex(['2008-05-02', '2008-05-05', '2008-05-06', '2008-05-07',
                '2008-05-08', '2008-05-09', '2008-05-12', '2008-05-13',
                '2008-05-14', '2008-05-15',
                ...
                '2019-11-01', '2019-11-04', '2019-11-05', '2019-11-06',
                '2019-11-07', '2019-11-08', '2019-11-11', '2019-11-12',
                '2019-11-13', '2019-11-14'],
               dtype='datetime64[ns]', name='Date', length=2906, freq=None)}

Looking at the web, I see that there are techniques for better formatting such axes: https://www.delftstack.com/howto/matplotlib/how-to-rotate-x-axis-tick-label-text-in-matplotlib/#fig-autofmt-xdate-rotation-to-rotate-xticks-label-text

Revised using a rotation argument for the xticklabels:

Thoughts on implementation

We look at the label of the x axis, and if it is a DateTimeIndex, we automatically use one of these techniques.

Note: this advice applies only to the matplotlib back-end – I don’t know enough about bokeh to know if there is a corresponding technique there.

[agustinaarroyuelo]

Hi! I am taking a look at this right now. Meanwhile, this should work:

ax = az.plot_trace(trace_cat) [ticks.set_rotation(45) for ticks in ax.figure.axes[0].get_xticklabels()]

[aloctavodia]

Yeah, we should fix az.plot_trace, currently is only returning the last axes instead of all of them. Making further tweaking of the plot not possible. @agustinaarroyuelo Could you check this?