title: 4 Subplot Barcharts in Python
body: <p>I downloaded this example from matplotlib and changed a few things. </p>
  
  <p>So far, I plotted a bar chart with 4 different arrays that I applied on the y axis and the count of measurements on the x axis.
  Now I would like to plot 4 subplots, each subplot for one of the arrays.</p>
  
  <p>I have come to this point :</p>
  
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt
  
  n= 6
  
  m1 = (0.10,0.12,0.10,0.11,0.14,0.10)
  m2=(0.21,0.21,0.20,0.22,0.20,0.21)
  m3=(0.29,0.27,0.28,0.24,0.23,0.23)
  m4=(0.41,0.39,0.35,0.37,0.41,0.40)
  x=[1,2,3,4,5,6]
  
  fig, ax = plt.subplots()
  
  index = np.arange(n)
  bar_width = 0.2
  
  opacity = 0.4
  error_config = {'ecolor': '0.3'}
  r1 = ax.bar(index, m1, bar_width,
                   alpha=opacity,
                   color='b',
  
                   error_kw=error_config)
  
  r2 = ax.bar(index + bar_width, m2, bar_width,
                   alpha=opacity,
                   color='r',
  
                   error_kw=error_config)
  
  r3 = ax.bar(index + bar_width+ bar_width, m3, bar_width,
                   alpha=opacity,
                   color='y',
                   error_kw=error_config)
  r4 = ax.bar(index + bar_width+ bar_width+ bar_width, m4, bar_width,
                   alpha=opacity,
                   color='c',
                   error_kw=error_config)                 
  plt.xlabel('D')
  plt.ylabel('Anz')
  plt.title('Th')
  
  f, ((ax1, ax2), (ax3, ax4)) = plt.subplots(2, 2, sharex='col', sharey='row')
  
  ax1.plot(x,m1)
  ax2.plot(x,m2)
  ax3.plot(x,m3)
  ax4.plot(x,m4)
  
  plt.tight_layout()
  plt.show()
  </code></pre>
  
  <p>why can´t I just plot "ax1.plot(x,r1)  ax2.plot(x,r2)  ..."  although r1,r2 are defined as bars and what do I have to change??</p>