title: Pandas: how to plot a line in a scatter and bring it to the back/front?
body: <p>I have checked to the best of my capabilities but haven't found any <code>kwds</code> that allow you to draw a line (such as <code>y=a-x</code>) on a <code>pandas</code> scatter plot (not necessarily the line of best fit) and bring it to the back (or to the front).</p>
  
  <pre><code>#the data frame
  ax=df.plot(kind='scatter', x='myX', y='myY',title="Nice title", 
     xlim=[0,100],ylim=[0,100],figsize=(8,5), grid=True,fontsize=10)
  
  #the line
  lnsp=range(0,110,10)
  line=[100-i for i in lnsp] #line is y=100-x
  ax=line_df.plot(kind='line',color='r',ax=ax,legend=False,grid=True,linewidth=3)
  </code></pre>
  
  <p>Is there anything I can use? Or is it just the order in which the two things are drawn?</p>