为Pandas Dataframe中的每个重复行追加值/索引

duplicates = df.duplicated()

df['index'] = df.groupby(df.columns.tolist()).cumcount()

import pandas as pd

# 创建示例DataFrame
data = {'A': [1, 2, 3, 1, 2, 3],
        'B': [4, 5, 6, 4, 5, 6],
        'C': [7, 8, 9, 7, 8, 9]}
df = pd.DataFrame(data)

# 找到重复行
duplicates = df.duplicated()

# 为重复行追加索引
df['index'] = df.groupby(df.columns.tolist()).cumcount()

print(df)

   A  B  C  index
0  1  4  7      0
1  2  5  8      0
2  3  6  9      0
3  1  4  7      1
4  2  5  8      1
5  3  6  9      1