Error in numeric utils

Describe the bug

(Line 191 in numeric utils)[https://github.com/arviz-devs/arviz/blob/c5edec458316501b6a9b22a718e09aa06c7fd0ff/arviz/numeric_utils.py#L191] is as follows:

width = np.round(np.max([1, bins_sturges, bins_fd])).astype(int)

When I ran this as part of running the PyMC3 getting started notebook,

round(np.max([1, bins_sturges, bins_fd]))

evaluated to 1, and, apparently 1.astype(int) raises an AttributeError:

AttributeError: 'int' object has no attribute 'astype'

I don’t, unfortunately, know how to reproduce this: when I set values for these variables and run the code outside ArviZ and PyMC3, it works fine. This works:

    import numpy as np
    bins_sturges = 1.2598237927692393
    bins_fd = 0.27849533001676674
    width = np.round(np.max([1, bins_sturges, bins_fd])).astype(int)

Is there, perhaps, some state of numpy or the python interpreter that is set and causes this to break? It seems like somehow the value of the np.round() expression ends up being a python-native int, instead of a numpy value, but I don’t know how this could happen.

Additional context

arviz 0.8.3 pandas 1.0.5 numpy 1.19.0 pymc3 3.9.2 last updated: Sun Jul 12 2020

CPython 3.7.7 IPython 7.16.1 watermark 2.0.2

[rpgoldman]

… but it does happen to me every time I try to run the notebook.

[aloctavodia]

BTW I tried to reproduce it, running the notebook with two numpy versions. no luck.