如何展平 pandas 中的多级列

Question

Please see the data in excel above. When use df.columns this is the printout:

Index(['Country of Citizenship', '2015', 'Unnamed: 2', 'Unnamed: 3',
   'Unnamed: 4', 'Unnamed: 5', 'Unnamed: 6', 'Unnamed: 7', 'Unnamed: 8',
   'Unnamed: 9',
   ...
   'Unnamed: 108', 'Unnamed: 109', 'Unnamed: 110', 'Unnamed: 111',
   'Unnamed: 112', 'Unnamed: 113', 'Unnamed: 114', 'Unnamed: 115',
   'Unnamed: 116', 'Unnamed: 117'],
  dtype='object', length=118)

I want to turn this multi-level column into a single level column with column name changed as 2015-Jan. Thanks a lot for help

Answer 1

You can read a excel file into a pandas dataframe with multi-indexes, like with the following example:

import pandas as pd

df = pd.read_excel('your_file.xlsx', 
                   header=[0,1,2], 
                   index_col=[0])

If you want to know how to navigate and use multi-indexes i recommend: this

Alternatively there are also alot of Stackoverflow questions regarding Multiindex.

Its hard to show without example data, but basically to flatten the multiindex you can do this:

df.columns = df.columns.to_flat_index()