title: Matplotlib bar chart- some bars are not visible and seem to be of different width
body: <p>The problem is connected with the matplotlib bar chart. To be specific, when I draw a bar chart some of the bars are not visible.</p>
  
  <p>Dots and bars uses the same data series so should be in the same places
  <img src="https://i.stack.imgur.com/AMFBZ.jpg" alt="Dots and bars uses the same data series so should be in the same places">.</p>
  
  <p>I do not know what is the source of this problem that is why I am posting this question.
  I have also noticed that for the same plot, when I enlarge the window to the full screen the missing bars magically appears</p>
  
  <p>The same data series as in the first picture, just full screen window
  <img src="https://i.stack.imgur.com/xqpAU.jpg" alt="The same data series as in the first picture, just full screen window">.</p>
  
  <p>The same happens also when I change the color of the plot, so lets say I use:</p>
  
  <pre><code>artist = plot.bar(x_data_series, y_data_series, color="black")
  </code></pre>
  
  <p>Right now I have this not complete chart, but when I use (just setting the color for the second time right after):</p>
  
  <pre><code>artist = plot.bar(x_data_series, y_data_series, color="black")
  matplotlib.artist.setp(artist, color="black")
  </code></pre>
  
  <p>I get this: </p>
  
  <p>Now all bars are visible
  <img src="https://i.stack.imgur.com/YnCdw.jpg" alt="Now all bars are visible">.</p>
  
  <p>The same happens when I zoom in this incomplete chart: </p>
  
  <p>Here also all bars are visible
  <img src="https://i.stack.imgur.com/Ua8jM.jpg" alt="Here also all bars are visible">.</p>
  
  <p>What is more the "invisible bars", when they are visible, they seem to be a little bit thicker than the others, however they width in the artist properties is the same as you can see here: </p>
  
  <p>One of this bars is the thicker one and the other the "normal" one, both are 0.8 in width
  <img src="https://i.stack.imgur.com/Y5DEt.jpg" alt="One of this bars is the thicker one and the other the &quot;normal&quot; one, both are 0.8 in width">.</p>
  
  <p>Just to give you more information this is a graph embedded in the tkinter.
  Here are the figure, canvas, and axes (parent frame is just a frame in which the plot is placed):</p>
  
  <pre><code>figure = Figure(dpi=100)
  plot = figure.add_subplot(111)
  canvas = FigureCanvasTkAgg(figure, parent_frame)
  </code></pre>
  
  <p>The "work arounds" I have found are not satisfactory for me and I would really like to find the source of the problem, plus the width problem is something I can't figure out.</p>