如何将多行合并为一行并在Pandas中命名？

Question

I have a dataframe:

age sex country 
25   m   USA
30   f   Canada
65   f   china
42   m   Indonesia
32   f   mexico

I want to convert the country to 2 categories and then I want to generate 2 columns of dummy variables:

North America=(USA, Canada, Mexico).
Asia= (China, Indonesia)

Answer 1

You can make a single column named continent and get your result:-

df = pd.DataFrame(data = {'age':[25,23,26], 'sex':['m','f','f'], 'country': 
['mexico','china','usa']})

north_america = ['usa','mexico','canada']
asia = ['china','indonesia']

def change(country):
    if country in north_america:
        return "North America"
    elif country in asia:
        return "Asia"


df['continent'] = df['country'].apply(change)
df

Output

       age  sex country continent
   0    25  m   mexico  North America
   1    23  f   china   Asia
   2    26  f   usa North America