title: Python - Plot a log-log plot with matplotlib
body: <p>I simply want to plot "<strong>a vs b</strong>" in a <strong>log-log</strong> scaled plot, but I get an error.</p>
  
  <pre><code>import matplotlib.pyplot as plt
  
  a = [7255.151855, 231.589661, 9.365415, 0.55364, 1.5001, 0.006408, 0.001204, 0.000842]
  b = [0.212399, 0.393191, 0.727874, 1.347436, 2.494368, 4.617561, 8.548006, 15.824027]
  
  CyclesPerBlock = 219397
  LoadAmplitude = 4990
  
  a = [x*CyclesPerBlock for x in a]
  b = [y*LoadAmplitude for y in b]
  
  fig = plt.plot
  fig.set_xscale("log")
  fig.set_yscale("log")
  fig.set_xlim(1e-3, 1e4)
  fig.set_ylim(1e-1, 1e3)
  fig.set_aspect(1)
  fig.set_title("Calculation Results")
  
  fig.plot(a, b, "o-")
  plt.draw()
  plt.show()
  </code></pre>