Gary: did Todd's example help you enough to speed you on your way?
JDH
Well... I might say "yes", but you did put that word "speed" in there 
If I run his code, it updates 1.5 frame per second. If I change the two
calls to
manager.canvas._tkcanvas.after(100, updatefig)
to
manager.canvas._tkcanvas.after(1, updatefig)
there is no difference in the speed.
FWIW, I'm on an 850MHz WinXP. IIRC, I get the same performance under linux
on the same machine.
You got five frames per second? When you say you improved performance
"without text" do you mean that you didn't label the axes?
Aside: I see that he calls show() in each iteration, yet John says show()
should only be called once per script. Todd seems
to be on top of this, so I'll take his word as good. Todd uses a figure
manager. I can copy that code, but I don't know what I'm doing with it. I
don't know what a figure manager does.
Finally, I'm not sure what he meant by "re-registering the handler with each
cycle". Does this mean call ....after() ?
Oh ... one last thing, and maybe this is somehow relevant ... Todd's
program crashes on exit with message:
invalid command name "18438384callit"
while executing
"18438384callit"
("after" script)
...after which I'm dumped into python (interactive prompt).
-gary