The suggested solution works, but requires that the user pushes the ready button in the GUI and closes a second, empty, window manually. Therefore, I decided not to implement this suggestion. It is not possible to first do e.g. vehicle.plot('input') and then run the GUI. But there is also no reason why you would do this...
See: http://stackoverflow.com/questions/41742352/pyplot-interactive-mode-blocks-tkinter-radiobutton/
The suggested solution works, but requires that the user pushes the ready button in the GUI and closes a second, empty, window manually. Therefore, I decided not to implement this suggestion. It is not possible to first do e.g. vehicle.plot('input') and then run the GUI. But there is also no reason why you would do this...