PyCharm如何在macOS上创建与Matplotlib一起使用的virtualenv？

Question

I'm on macOS 10.14.3 using Python 3 installed via Homebrew, and I have installed virtualenv with pip :

$ brew install python
$ pip3 install virtualenv

Now the following issue is well documented and known not to work :

$ virtualenv venv
$ source venv/bin/activate
$ pip install matplotlib ipython
$ ipython
In [1]: %matplotlib

ImportError: Python is not installed as a framework. The Mac OS X backend will
not be able to function correctly if Python is not installed as a framework.
See the Python documentation for more information on installing Python as a
framework on Mac OS X. Please either reinstall Python as a framework, or try
one of the other backends. If you are using (Ana)Conda please install
python.app and replace the use of 'python' with 'pythonw'. See 'Working with
Matplotlib on OSX' in the Matplotlib FAQ for more information.

Now I noticed that if I create a virtualenv with PyCharm using "Create New Project" - "Pure Python" with "Project Interpreter" set to "New environment using Virtualenv", I can successfully use Matplotlib with any installed backend. Say the virtualenv created with PyCharm resides in the folder venv2 :

$ source venv2/bin/activate
$ pip install matplotlib ipython
$ ipython
In [1]: %matplotlib
Using matplotlib backend: MacOSX

Why does this work? How does PyCharm create the virtualenv so that Matplotlib works? Their docs state that they are also using the virtualenv package, so I have no clue what they do differently.

Answer 1

See https://matplotlib.org/faq/osx_framework.html

The solution is to not use virtualenv, but instead the stdlib's venv, which provides similar functionality but without exhibiting this issue.

It is a bug with virtual environment created with virtualenv command. PyCharm uses venv command as recommended in docs above.

If you create virtual environment in terminal using venv command, it should work without issues.