title: Choose matplotlib xticks frequency
body: <p>I am plotting data with strings as x labels. I'd like to control the label frequency to not overload the axis with text. In the example below i'd like to only see a label every 3 tick: a-d-g-j.</p>
  
  <p><a href="https://i.stack.imgur.com/W9DGd.png" rel="noreferrer"><img src="https://i.stack.imgur.com/W9DGd.png" alt="enter image description here"></a></p>
  
  <p>One way I could do that is to replace the my_xticks elements by 2 empty strings every n elements. 
  But i'm sure it gives a cleaner way to do that.</p>
  
  <p>Here is the code:</p>
  
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt
  
  y=np.array([4,4,4,5,5,6,5,5,4,4,4])
  x = np.arange(y.shape[0])
  my_xticks=['a','b','c','d','e','f','g','h','i','j','k']
  
  plt.xticks(x, my_xticks)
  plt.plot(x, y)
  </code></pre>