如何安装 scikit-image？

Question

它的scikit-image Download说：

pip install -U scikit-image

或者

easy_install -U scikit-image

但无论标志 U 是什么，都失败了，如下所示：

Georgioss-MacBook-Pro:Downloads gsamaras$ sudo pip install scikit-image
The directory '/Users/gsamaras/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.
The directory '/Users/gsamaras/Library/Caches/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Collecting scikit-image
  Downloading scikit_image-0.12.3-cp27-cp27m-macosx_10_6_intel.macosx_10_9_intel.macosx_10_9_x86_64.macosx_10_10_intel.macosx_10_10_x86_64.whl (22.2MB)
    100% |????????????????????????????????| 22.2MB 53kB/s 
Requirement already satisfied: dask[array]>=0.5.0 in /Library/Python/2.7/site-packages (from scikit-image)
Collecting six>=1.7.3 (from scikit-image)
  Downloading six-1.10.0-py2.py3-none-any.whl
Collecting networkx>=1.8 (from scikit-image)
  Downloading networkx-1.11-py2.py3-none-any.whl (1.3MB)
    100% |????????????????????????????????| 1.3MB 133kB/s 
Requirement already satisfied: pillow>=2.1.0 in /Library/Python/2.7/site-packages (from scikit-image)
Requirement already satisfied: numpy; extra == "array" in /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python (from dask[array]>=0.5.0->scikit-image)
Requirement already satisfied: toolz>=0.7.2; extra == "array" in /Library/Python/2.7/site-packages (from dask[array]>=0.5.0->scikit-image)
Collecting decorator>=3.4.0 (from networkx>=1.8->scikit-image)
  Downloading decorator-4.0.10-py2.py3-none-any.whl
Installing collected packages: six, decorator, networkx, scikit-image
  Found existing installation: six 1.4.1
    DEPRECATION: Uninstalling a distutils installed project (six) has been deprecated and will be removed in a future version. This is due to the fact that uninstalling a distutils project will only partially uninstall the project.
    Uninstalling six-1.4.1:
Exception:
Traceback (most recent call last):
  File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/basecommand.py", line 215, in main
    status = self.run(options, args)
  File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/commands/install.py", line 342, in run
    prefix=options.prefix_path,
  File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/req/req_set.py", line 778, in install
    requirement.uninstall(auto_confirm=True)
  File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/req/req_install.py", line 754, in uninstall
    paths_to_remove.remove(auto_confirm)
  File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/req/req_uninstall.py", line 115, in remove
    renames(path, new_path)
  File "/Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg/pip/utils/__init__.py", line 267, in renames
    shutil.move(old, new)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 302, in move
    copy2(src, real_dst)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 131, in copy2
    copystat(src, dst)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/shutil.py", line 103, in copystat
    os.chflags(dst, st.st_flags)
OSError: [Errno 1] Operation not permitted: '/tmp/pip-qlMJKP-uninstall/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/six-1.4.1-py2.7.egg-info'
Georgioss-MacBook-Pro:Downloads gsamaras$ 

和：

Georgioss-MacBook-Pro:Downloads gsamaras$ sudo easy_install scikit-image
Searching for scikit-image
Reading https://pypi.python.org/simple/scikit-image/
Best match: scikit-image 0.12.3
Downloading https://pypi.python.org/packages/86/d0/b0192dc9a544da90f2d9150bcd84b981c6873e42a1f752b6affb89180ad8/scikit-image-0.12.3.tar.gz#md5=04ea833383e0b6ad5f65da21292c25e1
Processing scikit-image-0.12.3.tar.gz
Writing /tmp/easy_install-X6Pjoh/scikit-image-0.12.3/setup.cfg
Running scikit-image-0.12.3/setup.py -q bdist_egg --dist-dir /tmp/easy_install-X6Pjoh/scikit-image-0.12.3/egg-dist-tmp-lHJxkL
Killed: 9

请注意brew，它也失败了，它找不到它。

我有 Python 2.7.10、Matplotlib 1.3.1、PIL 3.4.2 和 Scipy '0.18.1'。该怎么办？

Answer 1

在系统范围的 Python 上安装库通常是一个坏主意。改为为每个项目使用 virtualenv。

首先在 Mac 上全局安装virtualenv：

$ [sudo] pip install virtualenv

然后使用virtualenv命令创建 Python 可执行文件的新（副本）：

$ cd your/prefred/folder
$ virtualenv your_project

激活virtualenv：

$ source your_project/bin/activate

您的 virtualenv 已创建并激活（提示已更改以显示激活）。您可以在其中安装任何东西：

$ pip install -U scikit-image