title: How to add Matplotlib Colorbar Ticks
body: <p>There are many matplotlib colorbar questions on stack overflow, but I can't make sense of them in order to solve my problem.</p>
  
  <p>How do I set the yticklabels on the colorbar?</p>
  
  <p>Here is some example code:</p>
  
  <pre><code>from pylab import *
  from matplotlib.colors import LogNorm
  import matplotlib.pyplot as plt
  
  f = np.arange(0,101)                 # frequency 
  t = np.arange(11,245)                # time
  z = 20*np.sin(f**0.56)+22            # function
  z = np.reshape(z,(1,max(f.shape)))   # reshape the function
  Z = z*np.ones((max(t.shape),1))      # make the single vector to a mxn matrix
  T, F = meshgrid(f,t)
  fig = plt.figure()
  ax = fig.add_subplot(111)
  plt.pcolor(F,T,Z, norm=LogNorm(vmin=z.min(),vmax=z.max()))
  plt.xlim((t.min(),t.max()))
  mn=int(np.floor(Z.min()))        # colorbar min value
  mx=int(np.ceil(Z.max()))         # colorbar max value
  md=(mx-mn)/2                     # colorbar midpoint value
  cbar=plt.colorbar()              # the mystery step ???????????
  cbar.set_yticklabels([mn,md,mx]) # add the labels
  plt.show()
  </code></pre>