嵌套字典列表中的 pandas 多索引 DataFrame

Question

I have a list of nested dictionaries

lst = [{'a':{'aa':1,'ab':2},'b':{'ba':3,'bb':4}}]*2

I am struggling to get a pandas DataFrame with mutltiindex columns.

Currently I am doing:

pd.concat([pd.DataFrame.from_dict(dct,orient='index').stack().to_frame().T for dct in lst])

and the output is (and shall be)

But there got to be a simpler line I guess, this one is ugly, cannot figure out right now. Any help is welcome. Thx.

Answer 1

Use nested list with dict comprehension and then recreate MultiIndex :

df = pd.DataFrame([{(k,k1): v1 for k, v in x.items() for k1, v1 in v.items()} for x in lst])
df.columns = pd.MultiIndex.from_tuples(df.columns)
print (df)
   a     b   
  aa ab ba bb
0  1  2  3  4
1  1  2  3  4