title: Logscale plots with zero values in matplotlib
body: <p>I am currently using logscale in order to have greater possibilities of plotting my data. Nevertheless, my data consists also of zero values. I know that these zero values will not work on logscale as log(0) is not defined.</p>
  
  <p>So e.g.,</p>
  
  <pre><code>fig = plt.figure()
  ax = fig.add_subplot(111)
  ax.plot([0,1,2],[10,10,100],marker='o',linestyle='-')
  ax.set_yscale('log')
  ax.set_xscale('log')
  </code></pre>
  
  <p>completely omits the zero value. Is this behavior acceptable? At least there should be some kind of warning. I only recognized it by accident. Is there maybe also a way of plotting zero value data in logscale?</p>
  
  <p>Thanks!</p>
  
  <p>P.S.: I hope this fits to stackoverflow. I did not find a mailing list of matplotlib.</p>