Hi,

I'm new to both graph-tool and Ubuntu, which I'm installing it on (as a virtual machine on my Windows 10 computer).

I've downloaded graph-tool 2.27 in my 'downloads' folder, and then followed the install instructions at https://git.skewed.de/count0/graph-tool/wikis/installation-instructions: Installation via package managers

However, this produces some error messages. Do I need to locate some or all of the files I downloaded onto a specific location on my virtual machine?

Here's the output I get:

VirtualBox:/etc/apt$ sudo apt-get update

[sudo] password:

Hit:1 http://ie.archive.ubuntu.com/ubuntu bionic InRelease

Get:2 http://security.ubuntu.com/ubuntu bionic-security InRelease [83.2 kB]

Get:3 http://ie.archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB]

Get:4 http://ie.archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]

Ign:5 http://downloads.skewed.de/apt/raring raring InRelease

Err:6 http://downloads.skewed.de/apt/raring raring Release

404 Not Found [IP: 74.50.54.68 80]

Get:7 http://ie.archive.ubuntu.com/ubuntu bionic-updates/main amd64 Packages [351 kB]

Get:8 http://ie.archive.ubuntu.com/ubuntu bionic-updates/main i386 Packages [315 kB]

Get:9 http://ie.archive.ubuntu.com/ubuntu bionic-updates/main amd64 DEP-11 Metadata [146 kB]

Get:10 http://ie.archive.ubuntu.com/ubuntu bionic-updates/main DEP-11 48x48 Icons [39.1 kB]

Get:11 http://ie.archive.ubuntu.com/ubuntu bionic-updates/main DEP-11 64x64 Icons [73.9 kB]

Get:12 http://ie.archive.ubuntu.com/ubuntu bionic-updates/universe amd64 Packages [206 kB]

Get:13 http://ie.archive.ubuntu.com/ubuntu bionic-updates/universe i386 Packages [206 kB]

Get:14 http://ie.archive.ubuntu.com/ubuntu bionic-updates/universe amd64 DEP-11 Metadata [183 kB]

Get:15 http://ie.archive.ubuntu.com/ubuntu bionic-updates/universe DEP-11 48x48 Icons [168 kB]

Get:16 http://ie.archive.ubuntu.com/ubuntu bionic-updates/universe DEP-11 64x64 Icons [277 kB]

Get:17 http://ie.archive.ubuntu.com/ubuntu bionic-updates/multiverse amd64 DEP-11 Metadata [2,468 B]

Get:18 http://ie.archive.ubuntu.com/ubuntu bionic-backports/universe amd64 DEP-11 Metadata [5,100 B]

Reading package lists... Done

E: The repository 'http://downloads.skewed.de/apt/raring raring Release' does not have a Release file.

N: Updating from such a repository can't be done securely, and is therefore disabled by default.

N: See apt-secure(8) manpage for repository creation and user configuration details.

VirtualBox:/etc/apt$ sudo apt-get install python-graph-tool

Reading package lists... Done

Building dependency tree

Reading state information... Done

E: Unable to locate package python-graph-tool

Any idea what is going wrong here?