带有 MultiIndex 的 Pandas 数据框

Question

I have a dictionary with tuple key, and I want to make dataframe with multi index:

dct = {('a', 'b'): 1, ('a', 'c'): 2}
pd.DataFrame(dct, index=['x'])

It returns:

But when I put list of dicts:

dct = {('a', 'b'): 1, ('a', 'c'): 2}
pd.DataFrame([dct, dct], index=['x', 'y'])

It returns:

How do I keep indices nested using this code?

Ie it should returns:

Answer 1

you can simply not use a list of dicts to achieve your result. If the dictionary is simply just going to be repeated, pandas will do this automatically:

dct = {('a', 'b'): 1, ('a', 'c'): 2}
df = pd.DataFrame(dct, index=['x', 'y'])

print(df)
   a   
   b  c
x  1  2
y  1  2

If you want a different value in each row if your dataframe, you should do so within your dictionary:

dct = {('a', 'b'): [1, 3], ('a', 'c'): [2, 4]}
df = pd.DataFrame(dct, index=['x', 'y'])

print(df)
   a   
   b  c
x  1  2
y  3  4