Group by list python

Groupby and list

In [1]: df = pd.DataFrame( {'a':['A','A','B','B','B','C'], 'b':[1,2,5,5,4,6]})
        df

Out[1]: 
   a  b
0  A  1
1  A  2
2  B  5
3  B  5
4  B  4
5  C  6

In [2]: df.groupby('a')['b'].apply(list)
Out[2]: 
a
A       [1, 2]
B    [5, 5, 4]
C          [6]
Name: b, dtype: object

In [3]: df1 = df.groupby('a')['b'].apply(list).reset_index(name='new')
        df1
Out[3]: 
   a        new
0  A     [1, 2]
1  B  [5, 5, 4]
2  C        [6]

Source: stackoverflow.com

Group by list python

values = set(map(lambda x:x[1], mylist))
newlist = [[y[0] for y in mylist if y[1]==x] for x in values]

Source: stackoverflow.com

Similar codes

0 vote110 views1 answer
Python pyqt5 checkbox trigger
Python
38 votes113 views2 answers
How to get the contents of a txt file in python
Python
0 vote109 views1 answer
MIn-Max problem in python
Python
34 votes114 views4 answers
Save thing in pickle python
Python
0 vote109 views1 answer
Torch.utils.data.random_split(dataset, lengths)
Python
0 vote141 views1 answer
Python << meaning
Python
0 vote108 views1 answer
Facet grid, barplot, catplot
Python
-2 votes124 views3 answers
Python list of all characters
Python
3 votes119 views3 answers
Load saved model
Python
0 vote129 views1 answer
Removes all the elements from a linked list python
Python