title: Is a column in pandas.DF() monotonically increasing?
body: <p>I can check if the index of a pandas.DataFrame() is monotonically increasing by using is_monotonic method. However, I would like to check if one of the column value is strictly increasing in value(float/integer) ?</p>
  
  <pre><code>In [13]: my_df = pd.DataFrame([1,2,3,5,7,6,9])
  
  In [14]: my_df
  Out[14]: 
     0
  0  1
  1  2
  2  3
  3  5
  4  7
  5  6
  6  9
  
  In [15]: my_df.index.is_monotonic
  Out[15]: True
  </code></pre>