How to delete rows with values in the same list in Python?

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Here is the dataframe:

mat = {'f1': ['A aaa', 'B sss', 'C ddd', 'B bbb'], 'f2': ['F eee', 'B bbb', 'A aaa', 'B sss']}
dict = {'A': ['A aaa'], 'B': ['B bbb', 'B sss'], 'C': ['C ddd'], 'F': ['F eee', 'F aaa']}
df = pd.DataFrame(mat)

We can see that the key 'B' has a list as its value in the dictionary, where the list consists of two items. What I need to do is to delete rows with values of f1 and f2 in the same list. For example, the second row and the fourth row.

pandas delete-row dataframe dictionary python
1 Answers

You can rework your dictionary to map the keys from the values, then use a groupby to identify the rows with all unique values:

dic = {'A': ['A aaa'], 'B': ['B bbb', 'B sss'],
       'C': ['C ddd'], 'F': ['F eee', 'F aaa']}

dic2 = {v: k for k,l in dic.items() for v in l}
# {'A aaa': 'A', 'B bbb': 'B', 'B sss': 'B', 'C ddd': 'C',
#  'F eee': 'F', 'F aaa': 'F'}

out = df[df.stack().map(dic2).groupby(level=0).nunique().ne(1)]

alternative:

df2 = df.stack().map(dic2).unstack()
out = df[df2.ne(df2.iloc[:, 0], axis=0).any(1)]

output:

      f1     f2
0  A aaa  F eee
2  C ddd  A aaa
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