title: 2D histogram plot not filling with base color in matplotlib ply.hist2d when axis limits are set (required)
body: <p>I need my plots to completely fill with color. Adjusting xlim, ylim, only works works after, but it is apparently past the step where the plot is completely filled. In cases where data spans (0,360), (90,180), the fill is fine, but if the data is tighter, white space is present.</p>
  <p>They also need to all have the same axis limits, so they can be compared visually, so just letting it stay in auto mode isn't going to work.</p>
  <p>I'm considering and working on just trying to work on the background color of the plot area, but that is still behaving problematic when saving to a png.</p>
  <p>(Note: my filled example still has a sliver missing at the bottom)</p>
  <pre><code>import matplotlib.pyplot as plt
  import numpy as np
  
  X = []
  Y = []
  
  X, Y = np.loadtxt('dihedral.txt', delimiter=',', unpack=True)
  
  plt.hist2d(X, Y, bins=200, cmap='jet')
  cb = plt.colorbar()
  cb.set_label('counts in bin')
  
  plt.ylim(90, 180) 
  plt.xlim(0, 360)
  
  plt.title('title')
  plt.xlabel('dihedral angle')
  plt.ylabel('angle of bend')
  #plt.show()
  
  plt.savefig('dihedral.png', dpi=300)
  </code></pre>
  <p><a href="https://i.stack.imgur.com/fWjCw.png" rel="nofollow noreferrer">unfilled plot</a></p>
  <p><a href="https://i.stack.imgur.com/qwK0g.png" rel="nofollow noreferrer">desired example of filled plot</a></p>