在 Python Dataframe 循环中创建列名

Question

Seems quite simple, after I added a loop, I tried adding column names, but my code keeps failing. Can someone help me where I can add the columns?

    x = range(1,25)
    y = pd.date_range(start="2016-02-01", end="2016-02-29")
    d2 = pd.DataFrame([a, b] for a in x for b in y)

Answer 1

The following methods will help you:

# Add columns to dataframe
d2.columns =['a', 'b']

# Create dataframe with columns a and b
d2=pd.DataFrame([[a, b] for a in x for b in y], columns=['a', 'b']) 

OUTPUT:

      a          b
0     1 2016-02-01
1     1 2016-02-02
2     1 2016-02-03
3     1 2016-02-04
4     1 2016-02-05
..   ..        ...
691  24 2016-02-25
692  24 2016-02-26
693  24 2016-02-27
694  24 2016-02-28
695  24 2016-02-29