title: Converting s to h:m in y-axis in matplotlib (data_plot)
body: <p>This might be similar to this <a href="https://stackoverflow.com/questions/35663705/how-to-plot-time-on-y-axis-in-hm-format-in-matplotlib">problem</a> but mine is in the context of       plot_date.</p>
  
  <p><strong>UPDATE</strong></p>
  
  <pre><code>log = row[3]
  
  day = log.strftime("%Y%m%d")
  month = log.strftime("%m")
  month2 = log.strftime("%B")
  year = log.strftime("%y")
  times = to_seconds(log.strftime("%I:%M"))
  </code></pre>
  
  <p><code>log</code> is from the database records in <code>2016-10-28 20:53:26</code> format. </p>
  
  <pre><code>time3 =[29100.0, 28860.0, 29280.0, 37980.0, 29100.0, 24780.0, 29700.0, 29160.0, 29460.0, 29100.0, 28980.0, 33780.0, 29400.0, 29100.0, 29400.0, 30360.0, 6180.0, 28860.0, 29400.0, 4440.0, 29160.0, 29160.0]
  
  day3 = ['20161003', '20161004', '20161005', '20161006', '20161007', '20161009', '20161010', '20161011', '20161012', '20161013', '20161014', '20161017', '20161018', '20161019', '20161020', '20161021', '20161023', '20161024', '20161025', '20161026', '20161027', '20161028']
  
  plt.grid(True, which='both')
  plt.grid(b=True, which='major', color='k', linestyle='-')
  plt.grid(b=True, which='minor', color='k', linestyle='-', linewidth=0.1)
  plt.xticks(rotation='vertical',fontsize='small')
  plt.minorticks_on()
  plt.margins(0.01)
  
  plt.plot_date(x=day3,y=time3,color="red", linestyle='--', markersize=4)
  plt.ylabel("Time")
  plt.xlabel("Day")
  </code></pre>
  
  <p>attached is the sample output:</p>
  
  <p><a href="https://i.stack.imgur.com/qevXC.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qevXC.png" alt="enter image description here"></a></p>
  
  <p>I want to display the y-axis in H:m format.</p>