$ sudo apt-get remove dia2code 

Uninstall dia2code including dependent package

If you would like to remove dia2code and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove dia2code 

Use Purging dia2code

If you use with purge options to dia2code package all the configuration and dependent packages will be removed.

$ sudo apt-get purge dia2code 

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 dia2code 

See Also,