


How to set up a virtual environment in python? Steps to build a virtual environment in Python
The content of this article is about how to build a virtual environment in python? The steps to build a virtual environment in Python have certain reference value. Friends in need can refer to it. I hope it will be helpful to you.
1. Question: If you want to develop multiple different projects on one computer, you need to use different versions of the same package. If you use the above command to install or update in the same directory, The new version will overwrite the previous version, and other projects will not be able to run.
Solution: Virtual Environment
Function: Virtual Environment
Yes Build an independent python operating environment
so that the operating environment of a single project does not affect each other.
All virtual environments
are located in /home/ Hidden directory under
.virtualenvs
2. Build a virtual environment
Install the virtual environment
sudo pip install virtualenv # 安装虚拟环境 sudo pip install virtualenvwrapper # 管理虚拟环境
Installation After completing the virtual environment, if you are prompted that the mkvirtualenv command cannot be found, you must configure the environment variables:
# 1、创建目录用来存放虚拟环境 mkdir $HOME/.virtualenvs # 2、打开~/.bashrc文件,并添加如下: export WORKON_HOME=$HOME/.virtualenvs source /usr/local/bin/virtualenvwrapper.sh # 3、运行 source ~/.bashrc
Command to create a virtual environment:
Tips: If you do not specify the python version, it will be installed by default. It is the virtual environment of python2
# 在python2中,创建虚拟环境 mkvirtualenv 虚拟环境名称 # 在python3 中, 创建虚拟环境 mkvirtualenv -p python3 虚拟环境名称
Using the virtual environment
View the command of the virtual environment
workon 两次tab键
The command of using the virtual environment
workon 虚拟环境名称
Command to exit the virtual environment
deactivate
Command to delete the virtual environment
# 先退出再删除, deactivate rmvirtualenv 虚拟环境名称
Installing plug-ins in the virtual environment
workon 虚拟环境 # 进入创建的虚拟环境 pip install 安装包的名称 # 安装
View the installation package in the virtual environment
pip freeze
Related recommendations:
Using virtualenv to build in CentOS python3 environment
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