How to sort multiple columns in Python?

Question

I have a sample dataframe as below.

d={
    'Country' :['Bermuda','Australia','Switzerland','Norway','Iceland','United Kingdom','Denmark'],
    '1960':[231,3424,4354,857,644,2355,743],
    '1970':[8674,4364,564,7563,868,742,55],
    '1980':[44,5456,34556,34254,565,568,97],
    '1990':[23234,556,34,5656,67,89765,45],
    '2000':[343,6767,356,5657,324345,4566,346]
}

df=pd.DataFrame(d, columns=['Country','1960','1970','1980','1990','2000'])

It looks like this:

I want to show top-4 countries which have the highest values for each year as a result.

Expected results:

Answer 1

Another option using nlargest:

df.iloc[:,1:].apply(
    lambda col: df.Country.loc[col.nlargest(5).index].reset_index(drop=True)
)

#   1960            1970            1980            1990            2000
#0  Switzerland     Bermuda         Switzerland     United Kingdom  Iceland       
#1  Australia       Norway          Norway          Bermuda         Australia     
#2  United Kingdom  Australia       Australia       Norway          Norway        
#3  Norway          Iceland         United Kingdom  Australia       United Kingdom
#4  Denmark         United Kingdom  Iceland         Iceland         Switzerland   

Answer 2

You can do the following:

temp={}

l=[i for i in df.columns if i!='Country']

for i in l:
    temp[i]=list(df.sort_values(by=i, ascending=False)['Country'].iloc[:4])

res=pd.DataFrame(temp)

>>> print(res)
             1960       1970            1980            1990            2000
0     Switzerland    Bermuda     Switzerland  United Kingdom         Iceland
1       Australia     Norway          Norway         Bermuda       Australia
2  United Kingdom  Australia       Australia          Norway          Norway
3          Norway    Iceland  United Kingdom       Australia  United Kingdom

Answer 3

>>> df.set_index('Country').apply(lambda col: col.nlargest(4).index)         

             1960       1970            1980            1990            2000
0     Switzerland    Bermuda     Switzerland  United Kingdom         Iceland
1       Australia     Norway          Norway         Bermuda       Australia
2  United Kingdom  Australia       Australia          Norway          Norway
3          Norway    Iceland  United Kingdom       Australia  United Kingdom