title: how reduce the number of points of a waveform?
body: <p>I have this,    </p>
  
  <pre><code>f = audiolab.Sndfile('test.wav', 'r')
  data = f.read_frames(f.nframes, dtype=numpy.int16)
  
  pyplot.rcParams['figure.figsize'] = 10, 2
  pyplot.plot(data)
  pyplot.xticks([])
  pyplot.yticks([])
  pyplot.show()
  </code></pre>
  
  <p>but the ploting is slow and freeze the pc, hoy I can reduce the numbers of points or how can I increase the performance of the code?</p>