Remove the values in pandas column list that match another column in that same row-CodePudding

I have a pandas df where one of the columns is made up of lists. I want to remove the values in that list that match another column in that same row. Please note sometimes the 'similar_ids' is empty or only has one value. Example is below:

original

ID     similar_ids 
1       1, 234, 3215
2       2, 52, 1
3       49, 3
4       4
5

desired

ID     similar_ids 
1       234, 3215
2       52, 1
3       49
4       
5

CodePudding user response：

import pandas as pd

d = {'ID':[1, 2, 3, 4, 5], 'similar_ids':[[1, 234, 3215], [2, 52, 1], [49, 3], [4], []]}
df = pd.DataFrame(data=d)

for i in range(len(df['ID'])):
    if df['ID'][i] in df['similar_ids'][i]:
        df['similar_ids'][i].remove(df['ID'][i])

CodePudding user response：

df['similar_ids'] = df.apply(lambda row: [x for x in row.similar_ids if x != row.ID], axis=1)
print(df)

Output:

   ID  similar_ids
0   1  [234, 3215]
1   2      [52, 1]
2   3         [49]
3   4           []
4   5           []