title: How to plot an histogram of the maximum of different dates?
body: <p>I am trying to simply plot a histogram for the max value of different dates. I have a DataFrame with many columns including a column <code>date</code>and a column <code>Points</code>. First, I find the max <code>Points</code>for each date with this code:</p>
  
  <pre><code>maxnight=new.groupby(["date"], sort=False)["Points"].max()
  </code></pre>
  
  <p>and then I try to plot a histogram of those maxes; I would like to have on the y-axis the frequencies and on the x-axis the max values. I try:</p>
  
  <pre><code>plt.hist(maxnight)
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/sOHuS.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/sOHuS.png" alt="enter image description here"></a></p>
  
  <p>But, it does not work, because the smallest value should be 5 and the histogram shows some 0 and 2.5... I do not understand where they come from. I look through all the values in <code>maxnight</code> and there is no value under 5</p>
  
  <p>EDIT:
  I try with a dummy set of data and it is working. I then found the error is from some outliers that should be there, which is another problems elsewhere. </p>