Dataframe to List of List conversion based on the name of column in Python

Question

Input:
Dataframe

col1    col2
item1   10
item1   20
item1   25
item2   56
item2   36
item3   1

Output:
List of List

[[10,20,25],[56,36],[1]]

jezrael · Accepted Answer · 2019-05-16 10:16:12Z

2

Create Series of lists by groupby with GroupBy.apply and last convert it to list:

L = df.groupby('col1')['col2'].apply(list).tolist()
print (L)
[[10, 20, 25], [56, 36], [1]]

answered May 16, 2019 at 10:16

jezrael

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Comments

yatu · Accepted Answer · 2019-05-16 10:16:30Z

1

You can GroupBy col1 and extract lists from each group of on col2:

df.groupby('col1').col2.apply(list).values.tolist()
# [[10, 20, 25], [56, 36], [1]]

answered May 16, 2019 at 10:16

yatu

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