Pandas: Multilevel column names

Question

pandas has support for multi-level column names:

>>>  x = pd.DataFrame({\'instance\':[\'first\',\'first\',\'first\'],\'foo\':[\'a\',\'b         


        

Answer 1

No need to create a list of tuples

Use: pd.MultiIndex.from_product(iterables)

import pandas as pd
import numpy as np

df = pd.Series(np.random.rand(3), index=["a","b","c"]).to_frame().T
df.columns = pd.Multiindex.from_product([["new_label"], df.columns])

Resultant DataFrame:

  new_label                    
          a         b         c
0   0.25999  0.337535  0.333568

Pull request from Jan 25, 2014