Dear Tamas,
Following our previous conversation on this mail list, I decided to install igraph on the server of the University, it is a debian distribution. However, as I don't have sudo or su right, I think I cannot follow the normal way of installing igraph as it is described here:
http://igraph.wikidot.com/installing-python-igraph-on-linux/
I asked the computer department to add igraph to the python modules available, this is what they said:
"Unfortunately we can only install software directly from the official
Debian stable repositories onto this system, and there is no package for
this available there. However, you are welcome to install the module
into your home directory."
Can I find a description somewhere how I can install igraph module without sudo rights?