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Animations with matplotlib

For some reason this wasn't overly clear in the documentation, but a simple way to make an animation using the default backend in matplotlib is something like this:
from numpy import random, array, arange
import matplotlib.pyplot as plt


plt.ion()
print "starting"

x = arange(100)
y = 2*random.rand(100)

line, = plt.plot(x, y, 'd-')


for i in arange(1,200):
  y = y + random.rand(100) - 0.500000
  line.set_data(x, y)
  ax = line.get_axes()
  ax.relim()
  ax.autoscale_view()
  plt.draw()   # redraw the canvas

plt.show()
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