Pandas Dataframe: Split Multiple Columns Into Multiple Columns

I've a panda dataframe in this format. Var1 Var2 Var2 A [2016-09-26, 2016-08-25, 2016-08-06] [u'1', u'5', u'4'] B [2016-09-26

Solution 1:

If values in columns Var2 and Var3 are in lists, you can use numpy.repeat for repeat values by legths by str.len and flat values of nested lists by chain:

print (type(df.Var2.iat[0]))
<class 'list'>

print (type(df.Var3.iat[0]))
<class 'list'>

from  itertools import chain

df1 = pd.DataFrame({
        "Var1": np.repeat(df.Var1.values, df.Var2.str.len()),
        "Var2": list(chain.from_iterable(df.Var2)),
        "Var3": list(chain.from_iterable(df.Var3))})

print (df1)
  Var1        Var2 Var3
0    A  2016-09-26    1
1    A  2016-08-25    5
2    A  2016-08-06    4
3    B  2016-09-26    1
4    B  2016-08-25    5
5    B  2016-08-06    4