Pandas: compare list objects in Series

Solution 1:

Do not use list in cell, it creates a lot of problem for pandas. If you do need an object column, using tuple:

df.A.map(tuple).isin([(1,2)])
Out[293]: 
0     True
1    False
2    False
Name: A, dtype: bool
#df[df.A.map(tuple).isin([(1,2)])]

Solution 2:

You can use apply and compare as:

df['A'].apply(lambda x: x==[1,2])

0     True
1    False
2    False
Name: A, dtype: bool

print(df[df['A'].apply(lambda x: x==[1,2])])

        A
0  [1, 2]

Solution 3:

With Numpy arrays

df.assign(B=(np.array(df.A.tolist()) == [1, 2]).all(1))

        A      B
0  [1, 2]   True
1  [2, 4]  False
2  [3, 1]  False

Solution 4:

Using numpy

df.A.apply(lambda x: (np.array(x) == np.array([1,2])).all())

0     True
1    False
2    False