如何制作 0 和 1 的 dataframe 使得每个唯一值都是一列？

Question

I have the following df

Then I would like to transform df into df1 whose column are unique values of df . Take the first row of df as an example, its year is 2012 and its report is 4. then column year_2012 and column reports_4 take value 1. The other columns take value 0.

import pandas as pd
data = {'year': [2012, 2012, 2013, 2014, 2014], 
        'reports': [4, 24, 31, 2, 3]}
df = pd.DataFrame(data)

Could you please elaborate how to obtain such result?

Answer 1

This is pd.get_dummies :

cols = ['year', 'reports']

pd.concat([pd.get_dummies(df[col], prefix=col) for col in cols],
          axis=1)

Or even easier, credit goes to @ScottBoston :

pd.get_dummies(df, columns=df.columns)

Output:

   year_2012  year_2013  year_2014  reports_2  reports_3  reports_4  reports_24  reports_31
0          1          0          0          0          0          1           0           0
1          1          0          0          0          0          0           1           0
2          0          1          0          0          0          0           0           1
3          0          0          1          1          0          0           0           0
4          0          0          1          0          1          0           0           0