9.6 Creating Indicator Variables

You can extract dummy variables from string columns. For example if they are separated by a '|':

In [1]: s = pd.Series(['a', 'a|b', np.nan, 'a|c'])

In [2]: s.str.get_dummies(sep='|')
Out[2]: 
   a  b  c
0  1  0  0
1  1  1  0
2  0  0  0
3  1  0  1

String Index also supports get_dummies which returns a MultiIndex.

New in version 0.18.1.

In [3]: idx = pd.Index(['a', 'a|b', np.nan, 'a|c'])

In [4]: idx.str.get_dummies(sep='|')
Out[4]: 
MultiIndex(levels=[[0, 1], [0, 1], [0, 1]],
           labels=[[1, 1, 0, 1], [0, 1, 0, 0], [0, 0, 0, 1]],
           names=[u'a', u'b', u'c'])