python - pandas scatter plotting datetime

Question

I have a dataframe with two columns of datetime.time's. I'd like to scatter plot them. I'd also like the axes to display the times, ideally. But

df.plot(kind='scatter', x='T1', y='T2')

dumps a bunch of internal plot errors ending with a KeyError on 'T1'.

Alternatively, I try

plt.plot_date(x=df.loc[:,'T1'], y=df.loc[:,'T2'])
plt.show()

and I get 'Exception in Tkinter callback' with a long stack crawl ending in

return _from_ordinalf(x, tz)
  File "/usr/lib/python3/dist-packages/matplotlib/dates.py", line 224, in _from_ordinalf
microsecond, tzinfo=UTC).astimezone(tz)
TypeError: tzinfo argument must be None or of a tzinfo subclass, not type 'str'

Any pointers?

Answer 1

Not a real answer but a workaround, as suggested by Tom Augspurger, is that you can just use the working line plot type and specify dots instead of lines:

df.plot(x='x', y='y', style=".")