changing current axes


I started using matblotlib few days ago, and like it.
I encountered the following problem:

I have a figure with two subplots. I use the toolbar for going back and
forth after changing axes’ scales. I want to change something in the
graphs from time to time – like shifting some lines elsewhere
(by editing lines’ properties). By playing with this I found a strange
behaviour of the axes() command:

I thought that calling simple axes(‘existing axes instance’) should
only make the ‘existing axes instance’ current. But, at least for me,
this command also resets the possibility of using back & forward
buttons. Is this really wanted?

What I truly want to achieve is to be able to use those navigation
buttons independently on what is drawn in the axes – only taking care
of the scales. I use the first subplot for visualizing input data, the
second subplot for visualizing fft of the input data. I have two
additional vertical lines in the former plot for selecting the range of
the input data to be then passed to fft. I want to be able to change
scales of both graphs at any time and do not discontinue this ability
by adding new things to the graphs…

  1. is the described behaviour of axes() function intended?
  2. what events have some influence on navigation buttons?
  3. what shall I read in order to be able to exercise some control over the buttons?

Thank you a lot! :slight_smile:
Ruda Sykora