Python嵌套词典到pandas数据框架中

Question

嗨，大家好，我目前正在做我的学校项目，我需要将我的dic转换为dataframe，以便将其用于机器学习。

myDic = {
    'Acura': {
      'CL': {
        '2003': {
          'transmission': '4',
          'engine': '1',
          'drivetrain': 'NHTSA: 13',
          'wheels_hubs': 'NHTSA: 8',
          'seat_belts_air_bags': 'NHTSA: 6',
          'brakes': 'NHTSA: 6',
          'lights': 'NHTSA: 5',
          'body_paint': 'NHTSA: 2',
          'fuel_system': 'NHTSA: 2',
          'electrical': 'NHTSA: 2',
          'suspension': 'NHTSA: 2',
          'miscellaneous': 'NHTSA: 1',
          'steering': 'NHTSA: 1'
        },
        '2002': {
          'transmission': '2',
          'engine': 'NHTSA: 8',
          'brakes': 'NHTSA: 7',
          'electrical': 'NHTSA: 4',
          'accessories-interior': 'NHTSA: 3',
          'seat_belts_air_bags': 'NHTSA: 3',
          'suspension': 'NHTSA: 2',
          'drivetrain': 'NHTSA: 2',
          'body_paint': 'NHTSA: 1',
          'accessories-exterior': 'NHTSA: 1',
          'windows_windshield': 'NHTSA: 1',
          'fuel_system': 'NHTSA: 1',
          'steering': 'NHTSA: 1',
          'miscellaneous': 'NHTSA: 1'
        }
      }
    }
}

它是这样的。我可以搜索我的dic为 myDic['Acura']['CL']['2003'] 我的意思是'品牌'-'型号'-'年份'，它给出了汽车的问题。那么，我怎样才能将其转换为数据框架呢？栏目将是品牌，型号，年份和问题？

Answer 1

我假设你要找的是:

import pandas as pd 


restructure_dict = {
    (level1_key, level2_key, level3_key): values
    for level1_key, level2_dict in myDic.items()
    for level2_key, level3_dict in level2_dict.items()
    for level3_key, values in level3_dict.items()
}
df = pd.DataFrame(restructure_dict).T.reset_index()
df = df.rename(columns={'level_0': 'brand', 'level_1': 'model', 'level_2': 'year'})
print(df)

而输出将是：

   brand model  year transmission    engine drivetrain wheels_hubs seat_belts_air_bags    brakes    lights body_paint fuel_system electrical suspension miscellaneous  steering accessories-interior accessories-exterior windows_windshield
0  Acura    CL  2003            4         1  NHTSA: 13    NHTSA: 8            NHTSA: 6  NHTSA: 6  NHTSA: 5   NHTSA: 2    NHTSA: 2   NHTSA: 2   NHTSA: 2      NHTSA: 1  NHTSA: 1                  NaN                  NaN                NaN
1  Acura    CL  2002            2  NHTSA: 8   NHTSA: 2         NaN            NHTSA: 3  NHTSA: 7       NaN   NHTSA: 1    NHTSA: 1   NHTSA: 4   NHTSA: 2      NHTSA: 1  NHTSA: 1             NHTSA: 3             NHTSA: 1           NHTSA: 1

---

另一个可能的解决方案是：

import pandas as pd


restructure_dict = {
    (level1_key, level2_key, level3_key): values
    for level1_key, level2_dict in myDic.items()
    for level2_key, level3_dict in level2_dict.items()
    for level3_key, values in level3_dict.items()
}
df = pd.DataFrame(restructure_dict)
print(df)

输出结果是：

                          Acura          
                             CL          
                           2003      2002
transmission                  4         2
engine                        1  NHTSA: 8
drivetrain            NHTSA: 13  NHTSA: 2
wheels_hubs            NHTSA: 8       NaN
seat_belts_air_bags    NHTSA: 6  NHTSA: 3
brakes                 NHTSA: 6  NHTSA: 7
lights                 NHTSA: 5       NaN
body_paint             NHTSA: 2  NHTSA: 1
fuel_system            NHTSA: 2  NHTSA: 1
electrical             NHTSA: 2  NHTSA: 4
suspension             NHTSA: 2  NHTSA: 2
miscellaneous          NHTSA: 1  NHTSA: 1
steering               NHTSA: 1  NHTSA: 1
accessories-interior        NaN  NHTSA: 3
accessories-exterior        NaN  NHTSA: 1
windows_windshield          NaN  NHTSA: 1

---

另一个选择是上述结果的转置版本。

import pandas as pd 


restructure_dict = {
    (level1_key, level2_key, level3_key): values
    for level1_key, level2_dict in myDic.items()
    for level2_key, level3_dict in level2_dict.items()
    for level3_key, values in level3_dict.items()
}

df = pd.DataFrame(restructure_dict).T
print(df)

输出为：

              transmission    engine drivetrain wheels_hubs seat_belts_air_bags    brakes    lights body_paint fuel_system electrical suspension miscellaneous  steering accessories-interior accessories-exterior windows_windshield
Acura CL 2003            4         1  NHTSA: 13    NHTSA: 8            NHTSA: 6  NHTSA: 6  NHTSA: 5   NHTSA: 2    NHTSA: 2   NHTSA: 2   NHTSA: 2      NHTSA: 1  NHTSA: 1                  NaN                  NaN                NaN
         2002            2  NHTSA: 8   NHTSA: 2         NaN            NHTSA: 3  NHTSA: 7       NaN   NHTSA: 1    NHTSA: 1   NHTSA: 4   NHTSA: 2      NHTSA: 1  NHTSA: 1             NHTSA: 3             NHTSA: 1           NHTSA: 1