title: matplotlib line plot dont show vertical lines in step function
body: <p>I do have a plot that only consists of horizontal lines at certain values when I have a signal, otherwise none. So, I am looking for a way to plot this without the vertical lines. there may be gaps between the lines when there is no signal and I dont want the lines to connect nor do I want a line falling off to 0. Is there a way to plot this like that in matplotlib?</p>
  
  <p><a href="https://i.stack.imgur.com/nKSR3.gif" rel="noreferrer"><img src="https://i.stack.imgur.com/nKSR3.gif" alt="enter image description here"></a></p>
  
  <pre><code>self.figure = plt.figure()
  self.canvas = FigureCanvas(self.figure)
  axes = self.figure.add_subplot(111)
  axes.plot(df.index, df["x1"], lw=1.0, c=self.getColour('g', i), ls=ls)
  </code></pre>