Matplotlib does not work on Windows due to a problem importing PyQt5. I have included the traceback, the output of conda info, and the list of packages in the environment. I do not have PyQt5 ...
SKIPPED [11] /home/travis/build/matplotlib/matplotlib/lib/matplotlib/tests/test_backend_qt.py:31: Qt5 binding already imported SKIPPED [1] /home/travis/build ...