Specify Linux Package versions and Python Library Versions for Installation

apt-get-specify-package-version.md

Specify Package Version apt-get install

Installing a specific version

Install exactly the specified version, example:

# Installing exactly version '1.20.3-1ubuntu2' of wget
sudo apt-get install wget=1.20.3-1ubuntu2

Install the latest patch for the specified version, example:

# Installing latest patch for wget version '1.20' of wget
sudo apt-get install wget=1.20.*

Retrieving version number for installed package

Retrieve installed version for packages, examples:

# dpkg -s <package name or space separated list of package names> | grep 'Package\|Version'
dpkg -s wget | grep 'Package\|Version'
# Package: wget
# Version: 1.20.3-1ubuntu2

dpkg -s wget git | grep 'Package\|Version'
# Package: wget
# Version: 1.20.3-1ubuntu2
# Package: git
# Version: 1:2.25.1-1ubuntu3.2

pip-specify-library-version.md

Specify Python Library Version pip install

Detailed information: https://www.python.org/dev/peps/pep-0440/#compatible-release

Installing a specific version

Install exactly the specified version, example:

# Installing exactly version 1.21.3
pip install numpy==1.21.3

Install the latest patch for the specified version of a Python library, example:

Symbol	Major	Minor	Patch
==	#	.#	.*
>=	#	.#	.#
~=	#	.#	.#

# equivalent options
pip install libaray_name~=major.minor.patch
pip install libaray_name>=major.minor.patch
pip install libaray_name==major.minor.*

Example for installing NumPy

# Installing latest patch for numpy version 1.21
pip install numpy~=1.21.3

Retrieving version number for installed libary

# pip freeze | grep <library name>
pip freeze | grep numpy
# numpy==1.21.3