title: Python plot data against date
body: <p>I have a dataset:</p>
  
  <pre><code>          A     B      C    D    yearweek
      0    245    95    60    30   2014-48
      1    245    15    70    25   2014-49
      2    150   275   385   175   2014-50
      3    100   260   170   335   2014-51
      4    580   925   535  2590   2015-02
      5    630   126   485  2115   2015-03
      6    425    90   905  1085   2015-04
      7    210   670   655   945   2015-05
  </code></pre>
  
  <p>How to plot each value against 'yearweek'?</p>
  
  <p>I tried for example:</p>
  
  <pre><code>    import matplotlib.pyplot as plt
      import pandas as pd
  
      new = pd.DataFrame([df['A'].values, df['yearweek'].values])
      plt.plot(new)
  </code></pre>
  
  <p>but it doesn't work and shows</p>
  
  <pre><code>    ValueError: could not convert string to float: '2014-48'
  </code></pre>
  
  <p>Then I tried this:</p>
  
  <pre><code>    plt.scatter(df['Total'], df['yearweek'])
  </code></pre>
  
  <p>turns out:</p>
  
  <pre><code>    ValueError: could not convert string to float: '2015-37'
  </code></pre>
  
  <p>Is this means the type of yearweek has some problem? How can I fix it?</p>
  
  <p>Or if it's possible to change the index into date?</p>
  
  <p>￼</p>