title: How can I change the alpha value dynamically in matplotlib python
body: <p>I'm seeking how to change an alpha value dynamically which are already plotted.</p>
  
  <p>This is a kind of sample code I want to implement, but I know it is a wrong writing.</p>
  
  <pre><code>import matplotlib.pyplot as plt
  
  fig = plt.subplot(1, 1)
  
  for rate in [0.1 * x for x in range(10, -1, -1)]:
      plt.plot(range(0, 5), range(0, 5), color="r", alpha=rate)
      plt.pause(0.1)
  
  plt.show()
  </code></pre>
  
  <p>The purpose of this sample code is that I want to decrease the alpha as the processing go on and make the line vanish.</p>
  
  <p>Does somebody know a way to accomplish like this problem?
  Thank you.</p>