How to split a DataFrame column in python

Question

i have DataFrame column which i want to split. For example:

     0     1     2
0    a     b     c-d-e
1    f     g     h-i-j
2    k     l     m-n-o

The information is stored in a DataFrame. How can I change the dataframe to this?

     0     1     2     3     4
0    a     b     c     d     e
1    f     g     h     i     j
2    k     l     m     n     o

Thank you

Answer 1

You're looking for Series.str.split

>>> print df[2].str.split('-', expand=True)
   0  1  2
0  c  d  e
1  h  i  j
2  m  n  o

>>> pd.concat((df[[0, 1]], df[2].str.split('-', expand=True)), axis=1, ignore_index=True)
   0  1  2  3  4
0  a  b  c  d  e
1  f  g  h  i  j
2  k  l  m  n  o

If you're using pandas older than 0.16.1, you want to use return_type='frame' instead of expand=True

Answer 2

You can use DataFrame constructor:

print df

#   0  1      2
#0  a  b  c-d-e
#1  f  g  h-i-j
#2  k  l  m-n-o

df[[2, 3, 4]] = pd.DataFrame([ x.split('-') for x in df[2].tolist() ])
print df

#   0  1  2  3  4
#0  a  b  c  d  e
#1  f  g  h  i  j
#2  k  l  m  n  o