$ sudo apt-get remove gdl-astrolib 

Uninstall gdl-astrolib including dependent package

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

$ sudo apt-get remove --auto-remove gdl-astrolib 

Use Purging gdl-astrolib

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

$ sudo apt-get purge gdl-astrolib 

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 gdl-astrolib 

See Also,