将嵌套字典中的值附加到列表并将该列表转换为数据框答案

【问题标题】：append value in a nested dictionary to list and convert that list to dataframe将嵌套字典中的值附加到列表并将该列表转换为数据框
【发布时间】：2022-09-27 14:35:55
【问题描述】：

我有一个嵌套字典列表，如下所示：

keywords_data=[{\'vol\': 90500,
  \'cpc\': {\'currency\': \'$\', \'value\': \'4.64\'},
  \'keyword\': \'coronary artery disease\',
  \'competition\': 0.15,
  \'trend\': [{\'month\': \'September\', \'year\': 2021, \'value\': 90500},
   {\'month\': \'October\', \'year\': 2021, \'value\': 90500},
   {\'month\': \'November\', \'year\': 2021, \'value\': 90500},
   {\'month\': \'December\', \'year\': 2021, \'value\': 74000},
   {\'month\': \'January\', \'year\': 2022, \'value\': 90500},
   {\'month\': \'February\', \'year\': 2022, \'value\': 110000},
   {\'month\': \'March\', \'year\': 2022, \'value\': 110000},
   {\'month\': \'April\', \'year\': 2022, \'value\': 110000},
   {\'month\': \'May\', \'year\': 2022, \'value\': 90500},
   {\'month\': \'June\', \'year\': 2022, \'value\': 90500},
   {\'month\': \'July\', \'year\': 2022, \'value\': 90500},
   {\'month\': \'August\', \'year\': 2022, \'value\': 90500}]}]

我想将其转换为如下数据框


keyword                       month        year        value

coronary artery disease       september    2021         90500
coronary artery disease       october      2021         90500
coronary artery disease       november     2021         90500
.
.
.
.

我可以使用访问元素关键字和竞争和每次点击费用


vol = []
cpc = []
for element in keywords_data:
    vol.append(element[\"vol\"])
    cpc.append(element[\"cpc\"][\"value\"])

但是当我尝试使用相同的方法访问趋势下的月份时，它会抛出一个错误，指出列表索引必须是切片或字符串，而不是 str。

如上所示，如何将其放入数据框中？

标签： python pandas dictionary

【解决方案1】：

使用json_normalize：

df = pd.json_normalize(keywords_data, 'trend', ['vol', 'keyword', 'competition','cpc'])

df = df.join(pd.json_normalize(df.pop('cpc')).add_prefix('cpc.'))
print (df)
        month  year   value    vol                  keyword competition  \
0   September  2021   90500  90500  coronary artery disease        0.15   
1     October  2021   90500  90500  coronary artery disease        0.15   
2    November  2021   90500  90500  coronary artery disease        0.15   
3    December  2021   74000  90500  coronary artery disease        0.15   
4     January  2022   90500  90500  coronary artery disease        0.15   
5    February  2022  110000  90500  coronary artery disease        0.15   
6       March  2022  110000  90500  coronary artery disease        0.15   
7       April  2022  110000  90500  coronary artery disease        0.15   
8         May  2022   90500  90500  coronary artery disease        0.15   
9        June  2022   90500  90500  coronary artery disease        0.15   
10       July  2022   90500  90500  coronary artery disease        0.15   
11     August  2022   90500  90500  coronary artery disease        0.15   

   cpc.currency cpc.value  
0             $      4.64  
1             $      4.64  
2             $      4.64  
3             $      4.64  
4             $      4.64  
5             $      4.64  
6             $      4.64  
7             $      4.64  
8             $      4.64  
9             $      4.64  
10            $      4.64  
11            $      4.64

【讨论】：