title: writing greek letters with subscripts with matplotlib
body: <p>I have to use greek letter with subscript as axes label, so i thought to use Latex symbols. I am using the following code:</p>
  
  <pre><code>from matplotlib import rc
  rc('font',**{'family':'sans-serif','sans-serif':['Helvetica']})
  rc('text', usetex=True)
  </code></pre>
  
  <p>and in the plot I have, for example:</p>
  
  <pre><code>ylabel(r'$\boldsymbol{\delta_y}$')
  </code></pre>
  
  <p>It works fine, it is just slow (it take about 5 sec. to make a plot), I guess it is bacause python has to call an external package.</p>
  
  <p>Any chances I can make it faster?</p>
  
  <p>I am using python 2.6 </p>