Cannot save matplotlib animation with ffmpeg

Question

I am trying to save a simple matplotlib animation from Jake Vanderplas, but I keep getting OSError: [Errno 13] Permission denied.

I should note that I

Answer 1

I had garbling issues when I first (naively) tried to modify the working example of answer 3 to show the graph in realtime (as well as keep the movie).

Not quite right mods of answer 3 (which worked for me)

1. plt.ion() # interaction on
2. plt.draw() and plt.show() inside animate function, before return statent
3. frames=20, interval=200 to slow graph creation a bit, but still make a 4 second movie

Now plot shows up in a window as it is being created, but the output movie is garbled.

Correct step 2:

• 2a: plt.draw() inside animate function
• 2b: plt.show() just after the animate function

Now movie plays back ungarbled.