pandas多索引数据帧条件列连接

import pandas as pd

# 创建两个示例数据框
df1 = pd.DataFrame({'key': ['A', 'B', 'C', 'D'],
                    'value1': [1, 2, 3, 4]})
df2 = pd.DataFrame({'key': ['C', 'D', 'E', 'F'],
                    'value2': [5, 6, 7, 8]})

# 使用merge()函数进行条件列连接
result = pd.merge(df1, df2, on='key')

print(result)

  key  value1  value2
0   C       3       5
1   D       4       6

# 创建多索引数据框
arrays = [['A', 'A', 'B', 'B'], [1, 2, 1, 2]]
index = pd.MultiIndex.from_arrays(arrays, names=('key1', 'key2'))
df1 = pd.DataFrame({'value1': [1, 2, 3, 4]}, index=index)

arrays = [['B', 'B', 'C', 'C'], [1, 2, 1, 2]]
index = pd.MultiIndex.from_arrays(arrays, names=('key1', 'key2'))
df2 = pd.DataFrame({'value2': [5, 6, 7, 8]}, index=index)

# 使用merge()函数进行多索引条件列连接
result = pd.merge(df1, df2, on=['key1', 'key2'])

print(result)

           value1  value2
key1 key2                
B    1          3       5
     2          4       6