virtualenv usage
mkidr ~/pyenv
cd ~/pyenv
virtualenv pycaffe #it will setup a new python environtment named pycafffe
. pycaffe/bin/activate #it will activate your pycaffe dependent virtual environment( pycaffe in your shell )
deactiver #leave your current python environment
//then every package installed by python will be stored independently.
Reference:
http://*.com/questions/18966564/pip-freeze-vs-pip-list
https://virtualenvwrapper.readthedocs.io/en/latest/
pip更新软件包的源
mkdir ~/.pip
cd .pip
vim pip.conf
and add flowing source address
[global]
index-url = https://mirrors.ustc.edu.cn/pypi/web/simple/
当然也可以尝试aliyun的源
注：有时需要更新pip
pip -verbose install -U pip
系统python不是python2.7
如果系统是python 2.7，那么我们每个virtual python也是python 2.7
但如果系统本身不是我所需要用的python2.7，那么我们需要在本地也安装python 2.7，并且本地安装virtualenv使用我们本地安装的python 2.7
具体安装方法
cs4版本python安装
How to change python from UCS2 to UCS4
解决undefined reference to "PyUnicodeUCS4_*
mac版pyenv安装
安装pyenv
brew install pyenv
查看有哪些版本python可以安装
pyenv install --list
安装
pyenv install 2.7.12
查看当前安装了哪些版
pyenv versions
切换python版本
pyenv global 2.7.12