title: controlling the number of x ticks in pyplot
body: <p>I want to display all 13 x ticks, but the graph only shows 7 of them having two intervals.     </p>
  
  <blockquote>
  <pre><code>plt.locator_params(axis='x',nbins=13)
  </code></pre>
  </blockquote>
  
  <p>Why doesn't above code work??</p>
  
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt
  import pandas as pd
  import matplotlib.dates as dates
  
  y = [0, 0.86, 0.826, 0.816, 0.807, 0.803, 0.804, 0.803, 0.802,0.81, 0.813, 0.813, 0.813]
  
  times = pd.date_range('2015-02-25', periods=13)
  fig, ax = plt.subplots(1)
  fig.autofmt_xdate()
  
  xfmt = dates.DateFormatter('%d-%m-%y')
  ax.xaxis.set_major_formatter(xfmt)
  
  plt.locator_params(axis='x',nbins=13)
  
  ax.plot_date(times.to_pydatetime(), y, 'v-')
  ax.xaxis.set_minor_locator(dates.WeekdayLocator(byweekday=(1),
                                              interval=1))
  ax.xaxis.set_minor_formatter(dates.DateFormatter('%d\n%a'))
  ax.xaxis.grid(True, which="minor")
  ax.yaxis.grid()
  plt.tight_layout()
  plt.show()
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/4D3mb.png" rel="nofollow"><img src="https://i.stack.imgur.com/4D3mb.png" alt="enter image description here"></a></p>