在 Dataframe 中展开嵌套的 dict

Question

我想在将嵌套字典输出到 csv 之前重新格式化它。 我的嵌套字典：

review = {'Q1': {'Question': 'question wording','Answer': {'Part 1': 'Answer part one', 'Part 2': 'Answer part 2'} ,'Proof': {'Part 1': 'The proof part one', 'Part 2': 'The proof part 2'}},
      'Q2': {'Question': 'question wording','Answer': {'Part 1': 'Answer part one', 'Part 2': 'Answer part 2'} ,'Proof': {'Part 1': 'The proof part one', 'Part 2': 'The proof part 2'}}}

到目前为止我已经尝试过：

my_df = pd.DataFrame(review)
my_df = my_df.unstack()

然后分道扬镳：

Q1  Answer      {'Part 1': 'Answer part one', 'Part 2': 'Answe...
    Proof       {'Part 1': 'The proof part one', 'Part 2': 'Th...
    Question                                     question wording
Q2  Answer      {'Part 1': 'Answer part one', 'Part 2': 'Answe...
    Proof       {'Part 1': 'The proof part one', 'Part 2': 'Th...
    Question                                     question wording

但我希望它最终看起来像这样：

Index   Question                Answer          Proof
Q1      question one wording    Answer part 1   Proof part 1
Q1      question one wording    Answer part 2   Proof part 2
Q2      question two wording    Answer part 1   Proof part 1
Q2      question two wording    Answer part 2   Proof part 2

所以我需要将 Dataframe 中的嵌套字典融化/unstack/pivot/expand/other_manipulation_word。

我已查看此指南以获取指导，但无法将其应用于我自己的： Expand pandas dataframe column of dict into dataframe columns

Answer 1

这是一种可能的解决方案：

1) 使用 orient 'index' 创建初始 DataFrame

df = pd.DataFrame.from_dict(review, orient='index')

2) 使用Index.repeat、Series.str.len 和DataFrame.loc 创建最终DataFrame 的形状

df_new = df.loc[df.index.repeat(df.Answer.str.len())]

3) 通过传递给DataFrame 构造函数并使用stack 值来修复“答案”和“证明”列

df_new['Answer'] = pd.DataFrame(df.Answer.tolist()).stack().values
df_new['Proof'] = pd.DataFrame(df.Proof.tolist()).stack().values
print(df_new)

            Question           Answer               Proof
Q1  question wording  Answer part one  The proof part one
Q1  question wording    Answer part 2    The proof part 2
Q2  question wording  Answer part one  The proof part one
Q2  question wording    Answer part 2    The proof part 2