Python

Installing python

This document offers comprehensive guidelines for installing Python on Ubuntu. It discusses multiple installation methods, such as utilizing APT, Anaconda, or pyenv for Python version management. The document also provides detailed instructions for installing Anaconda, setting up a virtual environment with Anaconda, and installing and configuring pyenv for Python version and virtual environment management.

Installing python using apt

Before installing Python on Ubuntu, it is important to check if Python is already installed on your system. You can do this by running the following command:

python3 --version

If Python ^3.10 is not already installed, you have the option to use APT to install it on your system. To do so, please follow these steps:

To update the system repository list, use the following command:sudo apt install python3

sudo apt update

1. To set up Python, install the required dependencies using the following command:sudo apt

   sudo apt install build-essential libssl-dev zlib1g-dev libbz2-dev libreadline-dev libsqlite3-dev curl libncursesw5-dev xz-utils tk-dev libxml2-dev libxmlsec1-dev libffi-dev liblzma-dev

2. Install the latest version of Python with the command:

   sudo apt install python3
   python3 --version

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(Recommended) Using Anaconda or pyenv

Instead of directly installing Python on your system, it is recommended to use Python version management tools like Anaconda or pyenv.

Installing python using anaconda

Anaconda is a software package that includes Python and R programming languages. It is widely used in scientific computing for various fields like data science, machine learning, and large-scale data processing.

If you are using Linux and want to use GUI packages, you will need to install additional dependencies for Qt.

apt-get install libgl1-mesa-glx libegl1-mesa libxrandr2 libxrandr2 libxss1 libxcursor1 libxcomposite1 libasound2 libxi6 libxtst6

To install the latest version of Anaconda, follow these steps:

1. Download the latest version of Anaconda from the official website:shasum -a 256

   apt-get install libgl1-mesa-glx libegl1-mesa libxrandr2 libxrandr2 libxss1 libxcursor1 libxcomposite1 libasound2 libxi6 libxtst6

2. (Recommended) Ensure the integrity of the installer's data by verifying it with SHA-256. For additional details on hash verification, please refer to the documentation on cryptographic hash validation.

   shasum -a 256 /PATH/ANACONDA
   # Replace /PATH/FILENAME with your installation's path and filename.

3. Install Anaconda by running the downloaded installer :

   bash ~/PATH/TO/ANACONDA
   # bash ./Anaconda3-2023.09-0-Linux-x86_64.sh

4. Update all packages in Anaconda

   conda update --all

5. Set up a Python Virtual Environment using Anaconda :

   conda create -n <Environment Name> python=<Version>
   # e.g., conda create -n Liberate python=3.11

6. Activate the virtual environment :

   conda activate <Environment Name>
   # e.g., conda activate Liberate

For more information on how to use Anaconda and its features, please refer to the official documentation.

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Installing python using pyenv

Pyenv is a tool that enables you to conveniently handle multiple Python versions and virtual environments.

To configure pyenv, you can simply follow these steps :

1. Download pyenv using the following command:

   curl -L https://github.com/pyenv/pyenv-installer/raw/master/bin/pyenv-installer | bash

2. Update pyenv to the latest version :

   pyenv update

3. To ensure proper configuration, please add the necessary settings to your shell startup file (~/.bashrc, ~/.zshrc, etc.), based on your shell environment.

   • For Bash :

     echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.bashrc
     echo 'command -v pyenv >/dev/null || export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bashrc
     echo 'eval "$(pyenv init -)"' >> ~/.bashrc
     

   • For Zsh :

     echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.zshrc
     echo '[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.zshrc
     echo 'eval "$(pyenv init -)"' >> ~/.zshrc

4. To install the Python version you want, you can use pyenv. First check the available Python versions using the command pyenv install --list. Then, install a specific version by running the appropriate command.

   pyenv install --list
   pyenv install <PYTHON VERSION>
   # ex) pyenv install 3.11.6

5. To start, create a Python virtual environment and activate it :

   pyenv virtualenv <PYTHON VERSION> <VIRTULAENV NAME>
   # ex) pyenv virtualenv 3.11.6 liberate
   pyenv activate <VIRTUALENV NAME>
   # ex) pyenv activate liberate

To learn more about using pyenv and its features, please refer to the official documentation.