python pip install requirements.txt example
The requirements.txt file is used to list Python project dependencies. It can be installed in one click through pip install -r requirements.txt; 1. Use pip install -r requirements.txt to install dependencies; 2. It is recommended to create and activate the virtual environment first to avoid polluting the global environment; 3. Use pip list or pip show package name to verify the installation; 4. Use pip freeze > requirements.txt to generate a dependency list; 5. Development dependencies can be stored separately in requirements-dev.txt; 6. When installation fails, you can use domestic mirror source to accelerate, such as -i https://pypi.tuna.tsinghua.edu.cn/simple/. The entire process ensures that the project environment is quickly and reliably completed.
When you see the requirements.txt
file in a Python project, it usually contains a list of third-party packages that the project depends on. Use pip install
to install these dependencies in one click. Here is a complete example description.

✅ Basic commands
pip install -r requirements.txt
This command will read the requirements.txt
file in the current directory and install all the packages listed in it.
? Example: requirements.txt file content
Suppose you have a requirements.txt
file in your project directory, with the following content:

requests==2.31.0 flask>=2.0.0 numpy pandas==2.0.1 django[argon2]
this means:
- Install the exact version of
requests
2.31.0 - The version of
flask
installed should not be lower than 2.0.0 - Install the latest available version of
numpy
- Install the exact version of
pandas
2.0.1 - Install
django
and additionally installargon2
support (for password hashing)
?️ Practical operation steps
- Open the terminal (command line)
- Go to the project directory (make sure
requirements.txt
is in the current path)
cd /path/to/your/project
- Execute the installation command
pip install -r requirements.txt
? Tip: It is recommended to use virtual environment to avoid polluting the global Python environment.
# Create a virtual environment python -m venv venv # Activate the virtual environment# Windows: venv\Scripts\activate # macOS/Linux: source venv/bin/activate # Install the dependency on pip install -r requirements.txt
? Verify that the installation is successful
You can run the following command to view installed packages:
pip list
Or check for specific packages:
pip show requests
? Tips
If you want to generate your own
requirements.txt
, you can use:pip freeze > requirements.txt
It is recommended to use
requirements-dev.txt
to include development dependencies (such as testing tools, formatting tools, etc.):pip install -r requirements-dev.txt
If the installation fails, it may be a network problem. You can use the domestic mirror source to accelerate:
pip install -r requirements.txt -i https://pypi.tuna.tsinghua.edu.cn/simple/
Basically that's it. As long as there is a correct
requirements.txt
file,pip install -r requirements.txt
can help you quickly build the project environment.The above is the detailed content of python pip install requirements.txt example. For more information, please follow other related articles on the PHP Chinese website!

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