ImportError：没有名为 matplotlib 的模块

Question

几个月前，Matplotlib 运行良好。但现在我不断收到错误：

ImportError: No module named matplotlib

我再次使用 pip 安装了 matplotlib。它没有用。我使用了易安装。还是行不通。

pip安装给了

Requirement already satisfied (use --upgrade to upgrade): matplotlib in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib-1.5.0-py2.7-macosx-10.6-intel.egg
Requirement already satisfied (use --upgrade to upgrade): numpy>=1.6 in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): python-dateutil in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/python_dateutil-2.4.2-py2.7.egg (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): pytz in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pytz-2015.7-py2.7.egg (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): cycler in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/cycler-0.9.0-py2.7.egg (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): pyparsing!=2.0.0,!=2.0.4,>=1.5.6 in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pyparsing-2.0.6-py2.7.egg (from matplotlib)
Requirement already satisfied (use --upgrade to upgrade): six>=1.5 in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/six-1.10.0-py2.7.egg (from python-dateutil->matplotlib)

然后我用了

sudo -E pip install matplotlib --upgrade

之后我得到了

The directory '/Users/ruskin/Library/Logs/pip' or its parent directory is not owned by the current user and the debug log has been disabled.        Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/Users/ruskin/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has been disabled.   Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
You are using pip version 6.1.1, however version 7.1.2 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
The directory '/Users/ruskin/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.

它继续升级matplotlib，但最后我得到了

Requirement already up-to-date: python-dateutil in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/python_dateutil-2.4.2-py2.7.egg (from matplotlib)
Requirement already up-to-date: pytz in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pytz-2015.7-py2.7.egg (from matplotlib)
Requirement already up-to-date: cycler in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/cycler-0.9.0-py2.7.egg (from matplotlib)
Requirement already up-to-date: pyparsing!=2.0.0,!=2.0.4,>=1.5.6 in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pyparsing-2.0.6-py2.7.egg (from matplotlib)
Requirement already up-to-date: six>=1.5 in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/six-1.10.0-py2.7.egg (from python-dateutil->matplotlib)
Installing collected packages: numpy
  Found existing installation: numpy 1.9.1
 Uninstalling numpy-1.9.1:
  Exception:
  Traceback (most recent call last):
    File "/Library/Python/2.7/site-packages/pip/basecommand.py", line 246, in main
      status = self.run(options, args)
    File "/Library/Python/2.7/site-packages/pip/commands/install.py", line 352, in run
      root=options.root_path,
    File "/Library/Python/2.7/site-packages/pip/req/req_set.py", line 687, in install
      requirement.uninstall(auto_confirm=True)
    File "/Library/Python/2.7/site-packages/pip/req/req_install.py", line 730, in uninstall
      paths_to_remove.remove(auto_confirm)
    File "/Library/Python/2.7/site-packages/pip/req/req_uninstall.py", line 126, in remove
      renames(path, new_path)
    File "/Library/Python/2.7/site-packages/pip/utils/__init__.py", line 292, in renames
      shutil.move(old, new)
    File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 303, in move
      os.unlink(src)
  OSError: [Errno 13] Permission denied: '/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/numpy-1.9.1.dist-info/DESCRIPTION.rst'

Answer 1

在 OS X 上，永远不要以 root 身份安装 python 模块，这是永无止境的失败的捷径。

为pip 使用--user 参数以便仅为当前用户安装模块，例如：

localhost:~ sorins$ which python
/usr/local/bin/python

python -m pip install --user --upgrade matplotlib

另外，请确保您使用的是正确的 python 解释器，因为 pip 经常会发生混淆并将模块安装在 python PATH (sys.path) 中未包含的位置。