title: do not let matplotlib automatically adjust the order of x axis
body: <p>Here is my little data:</p>
  
  <pre><code>aa3=pd.DataFrame({'OfficeName':['Narre Warren','Cannington','Chadstone','1_Mean',
                              'Traralgon','Bondi Junction','Hobart','2_Mean'],
                'Ratio':[0.1,0.2,0.4,0.1,0.43,0.4,0.15,0.32]})
  </code></pre>
  
  <p>The order of OfficeName is exactly what I want. But, when I try to draw a bar chart:</p>
  
  <pre><code>plt.bar(aa3.loc[:,'OfficeName'],aa3.loc[:,'Ratio'])
  </code></pre>
  
  <p>The chart looks like this:</p>
  
  <p><a href="https://i.stack.imgur.com/iEfFH.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/iEfFH.jpg" alt="enter image description here"></a></p>
  
  <p>You can see that the order of x axis is automatically changed. This is really bad for my work. What I should do to make the chart show the bars just based on the order in my data?</p>