$ sudo apt-get remove pianobar 

Uninstall pianobar including dependent package

If you would like to remove pianobar and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove pianobar 

Use Purging pianobar

If you use with purge options to pianobar package all the configuration and dependent packages will be removed.

$ sudo apt-get purge pianobar 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove pianobar 

See Also,