How to remove repositories using command line in ubuntu

This is a simple tip that will show you how to remove ppa repositories,uninstall the package(s)(installed from this repositories) and restore the official package(s) from the official ubuntu repositories with one command . Everybody knows that in karmic the new magic command to add repositories is :

sudo add-apt-repository ppa:<repository-name>/<subdirectory>

you can add a repository easy way without using the old long methode : open  the sources.list and then add the 2 lines and then add the verification keys ….Now adding the repositories and installing the packages are easy, but did you think of the way how  to remove the added repositories and the unistall packages  ?

For example, we suppose that you added a repository and you installed the package< X> from this repository, the installed  packege will replace the default package <Y> from ubuntu oficiel repositories. Now  later you wanted to uninstall the installed package <X> and remove the repository, then restore the default package<Y> from default repositories of ubuntu.

The solution come from PPA-purge, a handy script that allows us to remove all the packages on Launchpad repository, disable this reposiotry and install all packages in the official repositories of their own version of Ubuntu.
All with the simple command :

sudo ppa-purge ppa:<repository-name>/<subdirectory>

You can download the PPA-purge .deb package from the official  link of PPA-purge launchpade and install it, then use the command above to remove the repositories

Thanks to : anxurweb, sourceslist

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