Ubuntu comes with Regina “out of the box” as part of its standard universe software collection. However, the version of Regina that ships with each Ubuntu release is fixed (e.g., Ubuntu 20.04 ships with Regina 5.1, and Ubuntu 22.04 ships with Regina 7.0).
If you wish to keep up-to-date with the newest version of Regina, follow the instructions below.
Note: On Ubuntu 22.04 LTS (jammy) and later, if you try to view
documentation through the Help menu, you may see a “File
not found” error. This is because Ubuntu now ships Firefox as a
snap (not a regular package), which cannot read locally installed
HTML files.
Regina simply asks the desktop environment (e.g., GNOME or KDE) for your
preferred HTML viewer. Therefore, if you wish to fix this, the best suggestion
for now is to change the file associations in your desktop settings
so that HTML files are opened by a different browser (one that actually has
permissions to read locally installed documentation).
Alternatively, you can always
read the handbook online here and
read the API documentation online here.
You only need to follow these installation steps the first time you install Regina. After this, Ubuntu's package manager will handle upgrades for you, just like for any other Ubuntu package.
The instructions below only install the main packages regina-normal and regina-normal-doc, which is all that most people will need. If you are a C++ programmer and you wish to build Regina into your own projects, you should also install the package regina-normal-dev.
Install the debian-keyring package. This will give you Regina's cryptographic signing key (since Ben is a Debian developer). To do this, type:
sudo apt-get install debian-keyring
Download Regina's repository description, according to your version of Ubuntu:
Ubuntu 23.04 (lunar): regina-lunar.sources
Ubuntu 22.10 (kinetic): regina-kinetic.sources
Ubuntu 22.04 LTS (jammy): regina-jammy.sources
Ubuntu 20.04 LTS (focal): regina-focal.sources
Copy the file you just downloaded into Ubuntu's sources directory /etc/apt/sources.list.d/, as shown below (replacing ~/Downloads/regina-VERSION.sources with the location of the file you downloaded):
sudo cp -i ~/Downloads/regina-VERSION.sources /etc/apt/sources.list.d/
Note the suffix .d on the directory name! You do not want to overwrite sources.list.
Update the list of available packages. To do this, type:
sudo apt-get update
If you see an error like “the public key is not available”, it may be because you forgot to install debian-keyring in the first step.
Install or upgrade Regina like you would any other package. Type:
sudo apt-get install regina-normal
If you had previously added Regina's repository as a single line in /etc/apt/sources.list (possibly via the graphical Software & Updates application), you can delete that older entry now. The new file that you just downloaded encodes the same repository but with better security. (The old source will still work, so there is no urgency to change.)