creating multiple rows from multiple list using same Id, pandas

Question

I have a sample dataframe like this, Column: ID and Main

ID,Main
0,[30 115 266 38;662 99 1199 43] [511 133 25 47] [664 162 49 22]

How do I make my dataframe something like below using pandas

Expected Output

ID,Main
0,30 115 266 38
0,662 99 1199 43
0,511 133 25 47
0,664 162 49 22

Answer 1

First replace ; by ][ and then extract values between [] by findall for Series of lists.

Last create DataFrame, reshape by stack with some data cleaning by reset_index:

s = df['Main'].fillna('').str.replace(';','][').str.findall('\[(.*?)\]')
df = (pd.DataFrame(s.values.tolist(), index=s.index)
        .stack()
        .reset_index(level=1, drop=True)
        .reset_index())
df.columns = ['ID','Main']
print (df)
   ID            Main
0   0   30 115 266 38
1   0  662 99 1199 43
2   0   511 133 25 47
3   0   664 162 49 22

Another solution for Series:

s = df['Main'].fillna('').str.strip('[]').str.split(';|\]\s+\[')