Ok, ok, I have solved my problem. In Ubunut 7.10 the default GUI-backend for matplotlib was TKagg, in 8.04 it is GTKagg,
which needs a special python shell to work correctly in interactive mode.
So I switched back to TKagg and everything works in the right manner.
Ok, ok, I have solved my problem. In Ubunut 7.10 the default GUI-backend for matplotlib was TKagg, in 8.04 it is GTKagg,
which needs a special python shell to work correctly in interactive mode.
So I switched back to TKagg and everything works in the right manner.