title: Date axis in heatmap seaborn
body: <p>A little info: I'm very new to programming and this is a small part of the my first script. The goal of this particular segment is to display a seaborn heatmap with vertical depth on y-axis, time on x-axis and intensity of a scientific measurement as the heat function. </p>
  
  <p>I'd like to apologize if this has been answered elsewhere, but my searching abilities must have failed me.</p>
  
  <pre><code>sns.set()
  nametag = 'Well_4_all_depths_capf'
  Dp = D[D.well == 'well4']
  print(Dp.date)
  
  
  heat = Dp.pivot("depth",  "date", "capf")
  ### depth, date and capf are all columns of a pandas dataframe 
  
  plt.title(nametag)
  
  sns.heatmap(heat,  linewidths=.25)
  
  plt.savefig('%s%s.png' % (pathheatcapf, nametag), dpi = 600)
  </code></pre>
  
  <p>this is the what prints from the ' print(Dp.date) '
  so I'm pretty sure the formatting from the dataframe is in the format I want, particularly Year, day, month.</p>
  
  <pre><code>0    2016-08-09
  1    2016-08-09
  2    2016-08-09
  3    2016-08-09
  4    2016-08-09
  5    2016-08-09
  6    2016-08-09
           ...    
  </code></pre>
  
  <p>But, when I run it the date axis always prints with blank times (00:00 etc) that I don't want.
  Is there a way to remove these from the date axis?</p>
  
  <p>Is the problem that in a cell above I used this function to scan the file name and make a column with the date??? Is it wrong to use datetime instead of just a date function?</p>
  
  <pre><code>D['date']=pd.to_datetime(['%s-%s-%s' %(f[0:4],f[4:6],f[6:8]) for f in             
  D['filename']])
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/joE8H.png" rel="noreferrer"><img src="https://i.stack.imgur.com/joE8H.png" alt="enter image description here"></a></p>