title: plotting repeated periodic solution
body: <p>I am trying to plot a repeated periodic solution using matplotlib in python.  I have the solution for one period, I have provided a sample test code below of the individual plot:</p>
  
  <pre><code>import matplotlib
  import numpy as np
  from matplotlib import pyplot as plt
  
  File1 = np.genfromtxt('File1.dat')
  
  fig,(ax1) = plt.subplots()
  fig.subplots_adjust(hspace=1.0)
  
  A1 = ax1.imshow(File1.T,extent=[-1,1,-1,1],cmap='coolwarm',origin='lower')
  cbar = fig.colorbar(A1,orientation = 'vertical')
  
  ax1.set_xticks([-1,0.0,1],minor=False)
  ax1.set_yticks([-1,0.0,1],minor=False)
  ax1.set_yticklabels(['$-1$','$0$','$1$'],minor=False)
  ax1.set_yticklabels(['$-1$','$0$','$1$'],minor=False)
  
  plt.xlabel('x', fontsize=22)
  plt.ylabel('y', fontsize=22)
  plt.title('Title', fontsize = 24)
  
  plt.show()
  </code></pre>
  
  <p>where the sample .dat file, File1.dat is given by</p>
  
  <pre><code>0.863  0.863  0.863  
  0.863  0.610  0.863  
  0.863  0.863  0.863 
  </code></pre>
  
  <p>I want to plot this periodic solution now repeatedly on the same plot.  To be specific, this plot ranges from x = [-1,1] and y = [-1,1], but  I want to make it range from x = [-20,20] and y = [-20,20] repeating this same solution over and over (periodically). </p>
  
  <p>How can I code this efficiently?  </p>
  
  <p>Copying the data in the .dat file may work for this simple example but my actual .dat file is very large and that method just isn't efficient. Thanks!</p>