`git-of-theseus-stack-plot cohorts.json` fails if using matplotlib 3

[calda]

Running git-of-theseus-stack-plot cohorts.json fails on the public release of macOS Mojave, running Python 3.7. On the other hand, git-of-theseus-survival-plot survival.json works just fine.

I'm getting a traceback with a TypeError:

$ git-of-theseus-stack-plot cohorts.json

Traceback (most recent call last):
  File "/usr/local/bin/git-of-theseus-stack-plot", line 11, in <module>
    sys.exit(stack_plot_cmdline())
  File "/usr/local/lib/python3.7/site-packages/git_of_theseus/stack_plot.py", line 79, in stack_plot_cmdline
    stack_plot(**kwargs)
  File "/usr/local/lib/python3.7/site-packages/git_of_theseus/stack_plot.py", line 56, in stack_plot
    pyplot.stackplot(ts, numpy.array(y), labels=labels, colors=colors)
  File "/usr/local/lib/python3.7/site-packages/matplotlib/pyplot.py", line 2836, in stackplot
    return gca().stackplot(x=x, *args, data=data, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/matplotlib/__init__.py", line 1785, in inner
    return func(ax, *args, **kwargs)
TypeError: stackplot() got multiple values for argument 'x'

And here is my cohorts.json:

{"y": [[2467, 3052, 3488, 3506, 3907, 4333, 2194, 2190, 2190, 2168, 2045, 2045, 1879, 1846, 1830, 1830, 1800, 1685, 1685, 1655, 1585, 1393, 1393, 1372, 1371, 1314, 1313, 1284, 1284, 1284, 1250, 1222, 1222, 1222, 1108, 1108, 1048, 802], [0, 0, 0, 0, 0, 0, 1282, 1337, 1337, 1496, 10367, 10948, 12419, 13469, 13642, 13859, 14026, 14467, 14471, 14727, 10163, 10957, 10976, 10961, 10940, 10874, 10833, 9934, 9931, 9931, 9894, 9660, 9650, 9611, 9219, 9219, 9082, 8748], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 203, 270, 755, 796, 1699, 1841, 1927, 2862, 4569, 4809, 5699, 6711, 6711, 7238, 7986]], "ts": ["2016-05-12T22:25:54", "2016-05-20T03:55:10", "2016-05-27T17:38:18", "2016-06-19T19:13:41", "2016-06-26T22:07:09", "2016-12-02T04:42:04", "2017-02-09T06:51:20", "2017-02-22T06:59:31", "2017-03-06T04:11:52", "2017-03-19T00:37:59", "2017-07-20T05:51:33", "2017-07-27T06:11:32", "2017-08-03T07:47:49", "2017-08-11T06:37:24", "2017-08-19T01:51:04", "2017-08-28T01:37:28", "2017-09-05T01:58:38", "2017-09-12T21:15:10", "2017-09-24T19:15:07", "2017-10-30T22:17:18", "2017-12-09T19:18:28", "2017-12-17T01:55:34", "2017-12-24T04:43:51", "2018-01-03T22:42:32", "2018-03-09T02:20:24", "2018-03-19T08:01:01", "2018-04-08T03:12:46", "2018-04-18T04:21:10", "2018-05-13T22:51:15", "2018-05-25T17:14:02", "2018-06-04T01:12:04", "2018-06-11T02:17:21", "2018-06-18T09:20:56", "2018-07-09T06:13:45", "2018-07-23T07:42:13", "2018-08-04T05:20:25", "2018-09-17T13:01:48", "2018-09-26T11:40:21"], "labels": ["Code added in 2016", "Code added in 2017", "Code added in 2018"]}

Let me know if there's any other information that would help!

[erikbern]

sounds like some python 3.7 issue

i guess we could add py37 to travis and see if it reproduces

[linusg]

Same here with Python 3.6.4 and matplotlib 3.0.0. I believe this is due to some (recent?) change in matplotlib, because when I

pip uninstall -y matplotlib && pip install -y matplotlib==2

the tool will happily create the requested plot!

$ ls -l stack_plot.png
ls: cannot access 'stack_plot.png': No such file or directory
$ git-of-theseus-stack-plot authors.json
$ ls -l stack_plot.png 
-rw-rw-r-- 1 linus linus 24890 Sep 28 09:25 stack_plot.png

[calda]

It does work correctly using matplotlib 2.2.3!