3D objects cannot be plotted with Matplotlib backend

[Henrik Finsberg]

The following code

import dolfin
dolfin.plot(dolfin.UnitCubeMesh(2, 2, 2))

Produces the following error message

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/henriknf/miniconda3/envs/pulse_new/lib/python3.7/site-packages/dolfin/common/plotting.py", line 438, in plot
    return _plot_matplotlib(object, mesh, kwargs)
  File "/Users/henriknf/miniconda3/envs/pulse_new/lib/python3.7/site-packages/dolfin/common/plotting.py", line 282, in _plot_matplotlib
    ax.set_aspect('equal')
  File "/Users/henriknf/miniconda3/envs/pulse_new/lib/python3.7/site-packages/matplotlib/axes/_base.py", line 1281, in set_aspect
    'It is not currently possible to manually set the aspect '
NotImplementedError: It is not currently possible to manually set the aspect on 3D axes

• FEniCS version 2019.1
• Matplotlib version 3.1.1
• Python 3.7.3
• macOS Mojave

[Amnon Harel]

Run into the same bug. Python 3.6.8, Ubuntu 18.04.1, brand new installation (mapplotlib also 3.1.1, FEniCS 2019.1.0)

[Wei Huang]

Please try to degrade your Matplotlib version by running conda install matplotlib=3.0.3 or pip3 install matplotlib=3.0.3

It works for me. I tested it.

[Kewei Li]

According to https://github.com/matplotlib/matplotlib/issues/1077, aspect='equal' is actually implemented wrongly in matplotlib right now, and should not be used. So that NotImplementedError in the newer version of matplotlib is correct. The suggested workaround is to use ax.auto_scale_xyz (suggested here: https://github.com/matplotlib/matplotlib/issues/1077#issuecomment-15389293). I think fenics should switch to that