python如将连续重复的某列值进行去重

Question

有一个dataframe生成代码如下

import pandas as pd
import numpy as np
dates = [i for i in range(1,26)]
print(dates)
df = pd.DataFrame(np.arange(50).reshape(25,2),index=dates, columns=['A', 'B'])
df.loc[5,['A']] = 20
df.loc[6,['A']] = 20
df.loc[6,['B']] = 33
df.loc[16,['A']] = 64
df.loc[16,['B']] = 65
df.loc[17,['A']] = 64
df.loc[17,['B']] = 65
df.loc[8:14,'A'] = 20   # 连续重复
df.loc[8:14,'B'] = 33    # 连续重复
df

    A    B    C
1    0    1    2
2    3    4    5
3    6    7    8
4    9    10    11
5    20    13    14
6    20    33    17
7    18    19    20
8    20    33    23
9    20    33    26
10    20    33    29
11    20    33    32
12    20    33    35
13    20    33    38
14    20    33    41
15    42    43    44
16    64    65    47
17    64    65    50
18    51    52    53
19    54    55    56
20    57    58    59
21    60    61    62
22    63    64    65
23    66    67    68
24    69    70    71
25    72    73    74

如何将其按A列进行分组将B列连续的重复的值进行去重只保留第一个,及最终结果如下

    A    B    C
1    0    1    2
2    3    4    5
3    6    7    8
4    9    10    11
5    20    13    14
6    20    33    17
7    18    19    20
8    20    33    23
9    42    43    44
10    64    65    47
11    51    52    53
12    54    55    56
13    57    58    59
14    60    61    62
15    63    64    65
16    66    67    68
17    69    70    71
18    72    73    74

Answer 1

用drop_duplicates就可以

result = df.drop_duplicates(['A', 'B'], keep='first')