Creating a Python virtual environment in UBUNTU14

First, install the PYTHON-VIRTUALENV package

sudo apt-get Install virtualenv

After the installation is complete, create a Virtual Environment folder.

mkdir venv
CD venv

Create a virtual environment, pure virtual environment, and the system inside the package without a little contact. Forvirtualenv1.7或者更新版本，这是默认行为。他会在当前目录中创建文件夹env

virtualenv--no-site-packages [Virtual environment name]
#例如env

Virtualenv--no-site-packages Env

To start the virtual environment, you need to activate

SOURCE Env/bin/activate

Notice that the command prompt is changed and has a (venv) prefix that indicates that the current environment is a venv python environment named.

You can install any package via PIP or sudo apt-get install, which is installed in the virtual environment and is not associated with the package in the System file library.

Launch a virtual environment

Deactivate

If you want to delete a virtual environment, simply delete the directory.

RM-RF env

Second, back up the current virtual environment, and store the list of packages needed for the current environment for the next construction of the same environment.

Pip Freeze > Requirements.txt

will produce a file Requirements.txt file.

If you want to build the same environment, just perform

Pip Install-r requirements.txt

Creating a Python virtual environment in UBUNTU14