python - 根据相同的键删除 Pandas 中的行

Question

如何删除 A 列是键的行，并且该键的任何行在 C 列中同时包含“foo”和“moo”

df_之前:

"cat"   |"waverly way"|"foo"|10.0
"cat"   |"smokey st"  |"moo"|9.7
"rabbit"|"rapid ave"  |"foo"|6.6
"rabbit"|"far blvd"   |"too"|3.2

df_after:

"rabbit"|"rapid ave"  |"foo"|6.6
"rabbit"|"far blvd"   |"too"|3.2

Answer 1

你可以这样做:

df.columns = ['A', 'B', 'C', 'D']

df:

        A            B    C     D
0     cat  waverly way  foo  10.0
1     cat    smokey st  moo   9.7
2  rabbit    rapid ave  foo   6.6
3  rabbit     far blvd  too   3.2

.

filter = ['foo,moo']
# used transform to concat all the values in column 'C' for a given 'A'
df['C'] = df[['A', 'B', 'C', 'D']].groupby(by=['A'])['C'].transform(lambda x: ','.join(x))

修改后的 df:

        A            B        C     D
0     cat  waverly way  foo,moo  10.0
1     cat    smokey st  foo,moo   9.7
2  rabbit    rapid ave  foo,too   6.6
3  rabbit     far blvd  foo,too   3.2

.

# applied negative mask to filter values with foo,moo in 'C'
df1 = df.loc[~df['C'].isin(filter)].reset_index(drop=True)

print(df1)

输出:

        A          B        C    D
0  rabbit  rapid ave  foo,too  6.6
1  rabbit   far blvd  foo,too  3.2